Search

Search Results

##search.searchResults.foundPlural##

Effect of Planting Density and Fertilizer Level on Growth and Yield of the Potato Variety KT4 in Thanh Tri, Hanoi

Nguyen Thi Thu Huong, Tran Thi Thiem

Date Received: 26-08-2019 / Date Accepted: 10-10-2019
This study was conducted to evaluate the effects of planting density and fertilizer level on the growth and yield of the potato variety KT4 grown in Thanh Tri, Hanoi. The field experiment was a split-plot designwith three replications. Plant density was main factor with3 levels: 4 tubers/m2(M1), 5 tubers/m2(M2) and 6 tubers/m2(M3); the sub-factor consisted of three fertilizer levels(kg/ha): 120N: 120P2O5: 120K2O (P1); 150N: 150P2O5: 150K2O (P2); 180N: 180P2O5: 180K2O (P3). Theresults showed that there weresignificant differences(P≤0.05)in plant height, leaf area index, dry matter, yield components and tuber yield when plant density increased from M1 to M2 and fertilizer application level increased from P1 to P2. However,there was no significant differencesin the above parameters between M1 and M2 as well as between P2 and P3. In addition, the effect of interaction between plant density and fertilizer level was significant for tuber yield. The highest tuber yield (26.21-27.44 tons per ha-1)was found at M2 and M3 density combining with P2 and P3 fertilizer leves.
Nitrogen Use Efficiency of Upland Rice in Northwest Region

Nguyen Van Khoa, Pham Van Cuong

Date Received: 15-09-2015 / Date Accepted: 29-11-2015
The efficiency of nitrogen fertilizer in upland rice variety “Nếp nương tròn” and the control variety LC93-1 was evaluated in a nethouse pot experiment at Tay Bac University in Son La city. The pots were filled with 5 kg of upland soil. Plants of two varieties were fertilized with five levels of nitrogen: 0 mgN/pot (N0), 200 mgN/pot (N1), 400 mgN/pot (N1), 600 mgN/pot (N3), and; 800 mgN/pot (N4). The experiment was designed in randomized complete blocks with three replications, each replication consisting of 3 pots. The result showed that increased amount of nitrogen fertilizer from 0 mg/pot (N0) to 800 mg/pot (N4) increased plant height, number of panicles/hill, number of filled grains/panicle, biomass and grain yield in both varieties. Increased level of nitrogenous fertilizer led to apparent increased nitrogen concentration in stems and leaves but litle in grains. However, the amount of nitrogen absorbed by stem, leaves and grains and the total amount of nitrogen increased with the increased level of nitrogen fertilizer applied. Nitrogen use efficiency (NUE), agronomic efficiency (AE), physiological efficiency (PE) and utilization efficiency (UE) of two varieties declined with increased amount of nitrogenous fertilizer. Highest utilization efficiency (UE) was obtained at low nitrogen level.
Evaluating the Nitrogen Fertilizer use Efficiency toward Reducing N2O Emission in Rice Production in the Red River Delta: A Case Study in Thuan Thanh, Bac Ninh

Phan Thi Hai Luyen, Nguyen Xuan Hoa

Date Received: 06-02-2025 / Date Published: 20-02-2025
The study aimed to evaluate the current status and factors affecting N use efficiency, thereby, proposing measures for improvement to reduce N2O emissions in rice production in the Red River Delta. The experiment was conducted on 30 farmers' production fields. In each field, one plot was designed without fertilization (control). Yield and amount of N absorbed in plants were analyzed to evaluate N use efficiency indicators. The results show that the current status of N recovery efficiency from fertilizers (ANR) and agronomic efficiency (AE) were low, 22.7 ± 5.5% and 15.94 ± 3.84kg grain/kg N, respectively. The factors that affect N use efficiency included N fertilizer level, rice variety, field size, and field elevation. At the current N fertilization level of 115kg N/ha, the amount of N2O emitted directly from fertilizer ứa recorded at 12.65kg N2O/ha, equivalent to 118,151kg N2O/year across the entire rice cultivation area of Thuan Thanh district. Research scenarios of reducing N fertilizer levels by 20-40% will correspondingly reduce 20-40% the amount of N2O emissions.
DOI: https://doi.org/10.1234/865stg19
Effect of N, P, K Levels and Timing of Topdressing on Growth, Yield and Economic Efficiency of Mungbean Grown in Thanh Hoa Coastal Sandy Soils

Nguyen The Anh, Vu Dinh Hoa, Nguyen Thi Chinh

Date Received: 18-07-2017 / Date Accepted: 30-08-2017
Identifying optimal fertilizer rate and frequency and timing of nitrogen and potassium split application presents one of the nutrient management measures for improvement of mungbean yield on sandy soil in general and on coastal sandy soil in Thanh Hoa province in particular. In the present study, the effect of three NPK rates (LL1, LL2, and LL3) and frequency and timing of NK split applications (TD1, TD2, and TD3) on plant growth, grain yield and economic efficiency of two mungbean varieties were studied. Mungbean cultivars ĐX208 and ĐX16 were grown on coastal sandy soils in the districts of Nga Son and Hoang Hoa and Tinh Gia, respectively, in 2012 and 2013 summer cropping seasons. Plant growth and yield were influenced by the level of fertilizer, timing and frequency of nitrogen and potassium top dress application. For cv. ĐX208, highest fertilizer rate (LL3) resulted in high yield although not significant compared with the control. Fertilizer rate LL3 with TD3 split application resulted in better growth and significantly higher yield as compared with the control (TD1). However, LL2 with TD2 split application brought about highest yield and economic return for ĐX 2008, while for shorter growth duration cv. ĐX16, LL2 with TD2 split applcation resulted in highest yield and economic return.
Influence of Nitrogen Fertilizer Rate on the Growth and Yield of Ly Son Garlic (Allium sativumL.) Plants in Sandy Soil at Quang Dien Commune, Thua Thien Hue Province

Phung Thi Bich Hoa, Pham Thanh

Date Received: 26-02-2020 / Date Accepted: 22-06-2020
Ly Son garlic (Allium sativumL.) is a high economic value crop. This is one of the first reports to evaluate the effect of nitrogen fertilizer application rate on the growth, development and yield of Ly Son garlic grown on the sandy soil inThua Thien Hue, Viet Nam. Four nitrogen fertilizer levelwere selected and tested in this study: 230kg N ha-1, 55kg N ha-1, 115kg N ha-1, 165kg N ha-1. Theresults showed that A. sativumwas suitable for growing and developing under the natural conditions of Thua Thien Hue. The growing duration of A. sativumranged from 120 to 145 days. Furthermore, the traditional fertilizer dosage (230kg N ha-1) gave the lowest yield;while, the nitrogen fertilizer level of 115kg N ha-1was the best treatment,which resulted inhigh yield and good growth in terms ofthe number of leaves per plant (6.1 leaves), pseudostem height (12.1cm), the weight of fresh bulb (5.73g), the weight of dry-bulb (0.45g) and the yield of A. sativum(6.03 t/ha), respectively. This result also demonstrated that the agro-biological characteristics, yield parameters such as bulb diameter and length, number of cloves per bulb of A. sativumplanted in that area have not been different comparing with the originally planted garlic grown in the areas of Ly Son, Quang Ngai province.
Effects of Nitrogen Level and Rhizosphere N2-FixingBacteria on Growth and Yield of Sesame (Sesamum indicumL.)

Tran Hoang Em, Le Vinh Thuc, Ly Ngoc Thanh Xuan, Tran Ngoc Huu, Nguyen Quoc Khuong

Date Received: 05-05-2021 / Date Accepted: 29-10-2021
The objective of this study was to determine the effect of nitrogen level and N-fixing rhizobacteria on growth and yield of sesame in undeposited alluvial soil. The experiment was arranged in a randomizedcompleteblock design with four replications. The first factor was nitrogen fertilizer levels (0, 50, 75 and 100%of recommendation rate);the second factor was application of bacteria: no rhizobacteria, a single strain AGVRB-07, single strain AGVRB-28,andthemixture of strains AGVRB-07 and AGVRB-28. The results showed that a reduction of nitrogen fertilizer application resulted in lower plant height, number of leaves per plant, leaf length, leaf width, number of flowers per plant, number of capsules per plant, capsule diameter, number of rows per capsule and grain yield. However, addition of N-fixing rhizobacteria as single strain AGVRB-07, AGVRB-28 or the mixture of AGVRB-07 and AGVRB-28 improvedplant height, number of capsules per plant and grain yield. The supplement of single strain or mixture of 2 strains also contributed to reducing approximately 25% of chemical nitrogen fertilizer as recommended, but sesame grain yield wasmaintained comparable to the full rate of nitrogen application.
Effects of Planting Density and Fertilizer Level on Growth, Development andProductivity of Honeysuckle (LonicerajaponicaThunb.) at Thanh Tri - Ha Noi

Ninh Thi Phip, Do Thi Be

Date Received: 26-04-2018 / Date Accepted: 09-10-2018
The present studywas to determineeffects of planting densityandlevel of NPK fertilizer on plant growth, productivity and medicinal quality and economic efficiency of honeysuckle (Lonicera JaponicaThunb.) in Thanh Tri -Ha Noi were studied. The experiment was designed according to a split-plot design with 3 replicationsat three NPK levels (P1, P2, P3)and four planting densities (M1, M2, M3, M4). The results showed that the plant growth, yield andmedicinalquality were influenced by planting density and the level of fertilizer. The plant grown at M2 (27,800 plants/ha, 60x60 cm) and fertilized withP3 (20 tons farmyard manure + 120 kg N/ha + 90 kg P2O5/ha + 120 kg K2O/ha)produced higher yield but lower loganin content compared to the other treatments. Plants grown with P1 (80 kg N/ha + 60 kg P2O5/ha + 80 kg K2O/ha)combined with M2 (27,800 trees/ha, 60x60 cm)produced good yield of medicinal material (34.70 quintals/ha), highest loganin content and highest loganin yiled.
Effects of Nitrogen, Phosphorus and Potassium Levelson Tomato Grown on Organic Substrate

Nguyen Van Thao, Nguyen Thu Ha, Do Nguyen Hai

Date Received: 21-04-2016 / Date Accepted: 15-07-2016 / Date Published: 13-06-2025
Nutrient supply to plants grown on substrate is necessary to obtain high product quality and yield. The objective of the present study was to determine the suitable amount of N, P, K fertilizers for tomato grown on organic substrate. The experiment consisted of 28 pots that were applied with different fertilizer levels. Study results show that pHKCl of organic substrate was neutral (7.28), total nitrogen, phosphorus and potassium were high and equivalent to some popular organic substrates. Different levels of phosphate, potassium fertilizer application (with the same level of nitrogen fertilizer) did not affect tomato yield. Combination of 6.0 g N, 4.5 g P2O5 and 6.0 g K2O per pot improved average fruit weight (78.32 g/fruit) and actual fruit yield (2.38 kg fruit/pot). Potassium fertilizer application significantly affected sugar content of tomatoes (> 5.0%) in pots applied with 4.0 - 6.0 g K2O. After 15 days of fertilization, NO3- content of the tomatoes fluctuated between from 29.7 to 110.3 mg/kg fruit which was lower than VietGap standard.
DOI: https://doi.org/10.31817/tckhnnvn.2016.14.8.
Affects Planting Density and Different Level of Nitrogen on Multiplication TheParent Lines of VNUA69 Waxy Maize Vatiety

Nguyen Van Ha, Nguyen Van Viet, Vu Thi Bich Hanh, Tran Thi Thanh Ha, Duong Thi Loan, Hoang Thi Thuy, Vu Van Liet

Date Received: 27-10-2017 / Date Accepted: 29-11-2017 / Date Published: 12-06-2025
The effect of fertilizer level and plant densities on seed production of the parentl lines of VNUA69 maize hybrid was investigated. A field experiment was conducted to evaluate the effect five densities(57, 62, 67, 72 and 80 thousand plantsper ha) with three levels of nitrogen application (120 kg N, 130 kg N, and 140 kg N per ha at a constant basal fertilizer of 80 kg P2O5 and 70 kg K2O per ha) on growth, development and yield of parentallines of the hybrid varietyVNUA69. Fertilizer levelsand plant densities affected plant height, yield and yield components of parentallinesdifferently. The yield of maleline D4 was 26.4 quintals per ha in Autumn-Winter 2016 and 27.6 quintals per ha in Spring season 2017 and of female line D6 was 28.6 quintals per ha in Autumn-Winter season 2016and30.3 quintals per ha Spring season 2017. The obtained results showed that appropriate planting density for both maize lines was 6.7 thousand per ha with 140 kg N per ha,80 kg P2O5and 70 kg K2O per hahectar basis.
DOI: https://doi.org/10.31817/tckhnnvn.2017.15.11.
Effects of Nitrogen FertilizerLevels on Content and Quality of Rice Bran Oil in JaponicaRice Line with Thick Aleurone Layer

Nguyen Hoang Phuong, Nguyen Thi Thu Hien, Nguyen Thi Quyen, Nguyen Duc Thuan, Nguyen Van Khoa, Pham Van Cuong

Date Received: 19-05-2023 / Date Accepted: 29-06-2023
A pot experiment was carried out in net house to evaluate the effect of nitrogen fertilization levels (0.5; 1.0 and 1.5g N per 0.03m2pot) on photosynthesis, grain yield and bran oil of the promising line with thick aleurone layer (Ja12) and the check variety (the original Mizuhochikara) in both autumn and spring season. The photosynthetic rate was measured in 5 plants of each treatment at flowering, milkand dough stages while whole plant dry matter accumulation was measured in five plants at effective tillering, booting, dough and mature stages. At the harvesting stage, the grain yield, ratio of bran/brown rice, and oil content were analysed in 20 plants of each treatment.The experiment results showed that photosynthesis rate and dry matter accumulation increased in both rice varieties with increasing N fertilizer level. The grain yield and characteristics related to oil quality including lipid content and γ-oryzanol content ofJa12 were higher than those ofthe check variety at all fertilizer levels in both cropping seasons. Increasing the amount of nitrogen fertilizer did not increase the ratio of bran/brown rice but increased the content of bran oil and the γ-oryzanol content in both rice varieties, especially the increase was much higher in Ja12 than that in Mizuchihokara variety in both cropping seasons.
Studies on Suitable NPK Fertilizer Dosage and N:P:K Ratio for Dien Pomelo (Citrus grandisL.) Growing on Acrisols in Chuong My District, Hanoi City

Ngo Thi Dung, Cao Viet Ha, Vu Thi Xuan, Nguyen Thu Ha

Date Received: 11-05-2022 / Date Accepted: 21-10-2022
The aim of this study was to determine the appropriate dosageand N:P:K ratioof fertilizer for Dien pomeloduring the production cycle on Acrisolsin Chuong Mydistrict, HaNoi. Ten experiments with different formulaswereconducted in2 years on 20-year-old Dien pomelo orchard. The efficiency of fertilizer was determined on the basis yield, quality and economic efficiency. The results showedthat the two formulas withthe highest yield and quality of pomelo were CT4formula(30kg Manure + 0.6kg N + 0.4kg P2O5+ 0.54kg K2O)/tree/year, with NPK ratio of 1:0.65:0.90 and CT6formula(30kg Manure + 0.75kg N + 0.38kg P2O5+ 0.56kg K2O)/tree/year,withNPK ratio of 1:0.50:0.75. The net yield in CT4 formula was28,425 (in 2020)and28,536 (in 2021) fruit/ha and in CT6formulawas28,074 (in 2020)and28,326 (in 2021) fruits/ha (average increase in 2 yearsfor CT4 and CT6 formula was 38.8% and 35.9%, respectively compared to that of the control). CT4 and CT6 formula also gave the best fruit quality with an average fruit height of 11.75cmand11.73cm,and averagefruit diameter of 13.74cm;averagedry matter content of 11.41%and 10.65%;average vitamin Ccontentof 80.0mg%and 73.1mg% and average Brix level of11.15%and 10.93%. In bothyears,2020 and 2021, CT4 yieldedthe highest economic efficiencywiththe averageprofit ofVND427.16 million/ha/year.
Efficiency of Organic Fertilizer Integration with Mineral Compounds and Vermicompost Amendments on the Growth and Yield of Rice Straw Mushroom (Volvariella volvacea) in Outdoor Conditions

Nguyen Hong Hue, Le Vinh Thuc, Tran Ngoc Huu, Nguyen Quoc Khuong

Date Received: 04-05-2020 / Date Accepted: 25-09-2020
The objective of this study was to determine the proper level of organic fertilizer integration with mineral compounds and vermicompost to improve the growth and yield of rice straw mushroom. A completely randomized block experiment was designed in outdoor condition with 8 treatments and 5 replications, each replication as a row length of 1.5m. The treatments included (1) supplement ofHVP 301.B 10g, (2) supplement ofHVP 301.B 20g, (3) supplement ofHVP 301.B: 30g, (4) supplement of vermicompost 10g, (5) supplement of vermicompost 30g, (6) supplement of vermicompost 50g, (7) supplement of vermicompost 70g, (8) no supplement of HVP 301.B and vermicompost. The results showed that rice straw mushroom cultivated in outdoor condition with supplement either organic fertilizer plus mineral compounds as HVP 301.B (10g) or vermicompost (70g) per 1.5m of bed length enhanced the length, width of the first 30 mushroom fruiting bodies (MFB), the number of MFB and mean weight per a MFB as compared to no supplement, therefore, the yields of mushroom on these treatments increased.
Lượng đạm bón ảnh hưởng đến sự phát triển của bộ rễ lúa trong điều kiện thiếu nước

Tran Thi Thiem, Yamauchi Akira2

Date Received: 30-11-2016 / Date Accepted: 27-03-2017 / Date Published: 06-08-2025
Nghiên cứu này được tiến hành nhằm đánh giá ảnh hưởng của lượng đạm bón đến sự phát triển bộ rễ được thể hiện qua tổng số chiều dài rễ, số rễ mọc từ mắt thân, chiều dài rễ mọc từ mắt và chiều dài rễ bên; lượng nước cây sử dụng và khả năng tích luỹ chất khô trong điều kiện độ ẩm đất khác nhau. Lúa được trồng trong hộp nhựa quan sát được sự phát triển của bộ rễ trong điều kiện nhà có mái che. Thí nghiệm gồm ba mức độ ẩm đất: tưới nước ngập (CWL), điều kiện thiếu nước (WD) ở 25 và 20% w/w độ ẩm đất. Thí nghiệp áp dụng 3 mức phân đạm bón: 30, 60 và 120 mg N cho mỗi hộp. Phân đạm được trộn đều với 80 mg P2O5 và 70 mg K2O và 2.5 kg đất khô trước khi gieo hạt. Kết quả thí nghiệm cho thấy, trong điều kiện thiếu nước (ở cả 25 và 20% w/w độ ẩm đất), khi tăng lượng đạm bón từ 30 lên 60 mg N đã làm tăng các chỉ tiêu về rễ, lượng nước cây sử dụng và khối lượng chất khô của cây, nhưng không có sự khác nhau về các chỉ tiêu trên khi tăng lượng đạm bón từ 60 lên 120 mg N. Tuy nhiên, trong điều kiện tưới ngập, các chỉ tiêu về rễ tăng dẫn đến cây hút được nhiều nước hơn, kết quả cây tích luỹ chất khô cao hơn khi tăng lượng đạm bón từ 30 lên 120 mg N. Hơn nữa, trong cả điều kiện tưới ngập và thiếu nước, tổng số chiều dài rễ có mối quan hệ thuận và chặt ở mức có ý nghĩa với lượng nước cây sử dụng.
DOI: https://doi.org/10.31817/tckhnnvn.2017.15.3.
Effect of Silicon Fertilizer Application on Growth and Anatomical Characteristics of Mondo grass (Ophiopogon JaponicusWall) underNon-irrigated Conditions at Ha Hoa District, Phu Tho Province

Nguyen Thi Thanh Hai, Nguyen Dinh Vinh, Nguyen Van Phu

Date Received: 24-06-2022 / Date Accepted: 27-09-2022
The study aimed to evaluate Mondo grass’s growth, productivity, and anatomical characteristics when fertilized with silicon under non-irrigated conditions. A two-factor experiment was conducted in Ha Hoa district, Phu Tho province according toa split-plot design on ferralic gray soil with 6 levels of silicon (0, 20, 30, 40, 50, 60kg SiO2/ha/year) and 2 varieties of Mondo grass (G2 and G6). The results showed that under non-irrigated conditions, the growth of the G6 variety was better than that of G2. The supplemental application of silicon brought about better effect on Mondo grass, increasing the depth and width of the root system, and the leaf area and enhancing the tillering ability and dry matter accumulation. The change in the anatomical structure of Mondo grass leaves and roots increases the ability of the plant to absorb and conduct water better. On haplic acrisols, the level of fertilizer application of 30kg N + 30kg P2O5+ 30kg K2O + 40kgSiO2/ha was is considered suitable for Mondo grass. At this level, the yield of Mondo grass was the highest (at 3.7 tons/ha), an increase by 27.6% compared to the non-silicon treatment. Therefore, the use of silicon supplements is recommended to reduce the harmful effects of water shortage on the growth and development of Mondo grass.
Effect of Urea, Urea-Plant Extracts on Growth and Yield of Bc15 Rice and Hn88 Corn

Nguyen Thi Phuong Thao, Le Thi Dung, Dang Van Son, Ninh Thi Thao, Nguyen Thi Thuy, Nguyen Trang Hieu, Nguyen Thanh Hai, Nguyen Tat Canh

Date Received: 04-07-2015 / Date Accepted: 05-05-2016 / Date Published: 12-06-2025
The use of plant extracts that inhibit soil urease activity to minimize of nitrogen losses is a potential strategy to reduce both production costs and environmental risks. This study evaluated the effects of crude plant extracts from Camellia sinensis and Hedyotis sp L. on nitrogen use efficiency of rice cv. BC15 and corn cv. HN88. For BC18 rice variety, there was no significant difference in stalk length, number of effective tillers, chlorophyll content, individual grain yield when applied with standard nitrogen fertilizer regime (100% urea) compared with 70% of standard level of urea combined with 3 ml crude plant extract as per 1 kg urea. For corn, there was no significant difference in days to emergence, days from sowing to tasseling and days from sowing to silking and yield when applied with standard nitrogen fertilizer regime compared with application of 70% of standard nitrogen level in combination with crude extract product of Camellia sinensis and Hedyotis sp L. Overall, combining crude extract of Camellia sinensis and Hedyotis sp L. with urea improves nitrogen use efficiency.
DOI: https://doi.org/10.31817/tckhnnvn.2016.14.4.
Effect of Potassium Levels on Root Yield and Quality ofJapanese Angelica (Angelica acutiloba (Sieb.et Zucc.) Kitagawa) in Phu Tho

Pham Thanh Loan

Date Received: 21-10-2022 / Date Accepted: 18-04-2023
The study aimed to determine the appropriate rate of potassium fertilizer to ensure high yield and quality of medicinal herbs, Japanese Angelica. The experiment consisted of 4 treatments arranged in a randomized complete block design. Root system, yield and content of extracts in the roots were evaluated. Results show that application of 120 K2O/ha resulted in optimum root growth, high individual dry and high extract content. This was also the level of fertilizer that gave the highest profit margin. The above results show that 120 K2O/ha is suitable for Japanese Angelica grown in Phu Tho.
Ảnh hưởng của mức đạm bón đến sinh trưởng của cây lúa trong các điều kiện hạn khác nhau

Tran Thi Thiem, Yamauchi Akira

Date Received: 10-08-2015 / Date Accepted: 29-11-2015
Nghiên cứu này nhằm mục đích đánh giá ảnh hưởng của lượng đạm bón đến sự phát triển bộ rễ, quang hợp và tích luỹ chất khô của cây lúa trong các điều kiện hạn khác nhau. Thí nghiệm được tiến hành trong nhà lưới dưới hệ thống tưới phun nước theo hàng tạo ra độ ẩm đất khác nhau. Ba mức phân đạm: 60, 120 và 180 kg N ha-1được trộn đều với 50 kg P2O và 50 kg K2O ha-1 và bón sau cấy 8 ngày. Kết quả thí nghiệm cho thấy, tổng chiều dài rễ và khối lượng chất khô tăng khi tăng lượng đạm ở mức bón 60 lên 120 kg N ha-1, nhưng khi tăng ở mức bón 120 lên 180 kg N ha-1không làm tăng các chỉ tiêu trên trong điều kiện hạn nặng (<17% w/w độ ẩm đất). Tuy nhiên, trong điều kiện hạn nhẹ (17-25% w/w độ ẩm đất) cũng như tưới nước đủ ẩm (>25% w/w độ ẩm đất), tổng chiều dài rễ tăng, cây hút nước nhiều hơn, quang hợp tốt hơn, dẫn đến cây tích luỹ chất khô cao hơn khi tăng lượng đạm bón từ 60 đến 180 N ha-1. Ngoài ra, chỉ trong điều kiện tưới nước đủ ẩm, tổng chiều dài rễ có mối quan hệ thuận và chặt ở mức ý nghĩa với khối lượng chất khô khi bón đạm ở mức bón 120 và 180 kg N ha-1, nhưng khi bón ở mức 60 kg N ha-1khối lượng chất khô không có mối quan hệ chặt ở mức ý nghĩa với tổng chiều dài rễ. Như vậy, trong điều kiện tưới nước đủ ẩm, việc bón đạm ở mức 120 và 180 kg N ha-1đều làm tăng khả năng tích luỹ chất khô do tổng chiều dài rễ tăng.
Effect of Different Levels of Nitrogen Application on Green Yield and Nutritive Value of Forage Sorghum (Sorghum bicolor (L.) Moench)

Tang Thi Hanh, Phan Thi Hong Nhung, Pham Van Cuong

Date Received: 31-03-2015 / Date Accepted: 21-04-2015
A field experiment was conducted from June to December in 2013 at Viet NamNational University of Agriculture to evaluate effect of four levels of nitrogen application (0 kgN, 120 kgN, 180 kgN, and 240 kgN per ha at a constant basal fertilizer of 120 kgP2O5and 120 kgK2O per ha) on growth, green fodder yield, and nutritive value of two sorghum cultivars, OPV21 and OPV88. Green yield and its related to parameters as well as nutritive value were determined at three cuttings: first cutting (90 days after sowing), second cutting (45 days after first cutting), and third cutting (45 days after second cutting). The obtained results showed that increase ofnitrogen level from 120 kgN to 180 kgN per ha did not lead to increased green yield. However, nutritive parameters,such as dry matter, total minerals, crude protein, and lipidsincreased while concentration of HCN decreased. At the second and third cutting, both of green yield and crop growth rate of OPV21 cultivar increased significantly with increasednitrogen applicationand concurrent rise inHCN concentration.The experiment suggested that the nitrogen level of 120 kg per ha should be applied for first cutting, whereas 180 kgN to 240 kgN per ha canbe appliedfor later cuttingsof OPV cultivars.
EFFECT OF INORGANIC NITROGEN FORMS AND CONCENTRATIONS ON GROWTH OF RICE GENOTYPES UNDER SEVERE SALINE CONDITION

Phan Thi Hong Nhung, Tang Thi Hanh, Pierre Bertin, Pham Van Cuong

Date Received: 10-02-2017 / Date Accepted: 03-04-2017 / Date Published: 06-08-2025
Các thí nghiệm được tiến hành trong điều kiện thủy canh và đồng ruộng nhằm đánh giá ảnh hưởng của ba liều lượng đạm và hai dạng đạm bón khác nhau là urê và amon nitrat đến sinh trưởng của các giống lúa trong điều kiện mặn cao. Thí nghiệm thủy canh được tiến hành với hai giống lúa chịu mặn là Cườm và A69-1, sử dụng dung dịch dinh dưỡng Yoshida có bổ sung muối NaCl với nồng độ 113 mM, xử lý đạm ở ba nồng độ là 1,4 mM N, 2,1 mM N, và 2,8 mM N. Cây lúa được đánh giá khả năng sinh trưởng ở thời điểm 4 tuần sau xử lý mặn. Ở thí nghiệm đồng ruộng, ba giống lúa địa phương gồm Cườm, Ngoi, Hom râu, và ba giống lúa cải tiến gồm A69-1, FL478 và IR28 được sử dụng để đánh giá sinh trưởng và năng suất dưới ảnh hưởng của ba liều lượng đạm bón là 45 kg N, 68 kg N, 90 kg N/ha ở điều kiện đất nhiễm mặn cao. Kết quả thí nghiệm thu được ở điều kiện thủy canh cho thấy các dạng đạm và liều lượng đạm bón ảnh hưởng theo chiều hướng khác khau đến sinh trưởng của cây lúa. Cụ thể, khi tăng lượng đạm bón, khối lượng chất khô tích lũy, số lượng rễ, tổng chiều dài rễ và giá trị SPAD tăng ở dạng đạm amon nitrat nhưng lại giảm ở dạng đạm urê cùng với chỉ tiêu chỉ số độ dày lá và hiệu suất sử dụng đạm ở cả hai giống lúa chịu mặn. Ở thí nghiệm đồng ruộng, việc thay đổi liều lượng và dạng đạm bón không ảnh hưởng đến năng suất thực thu. Tuy nhiên, dạng đạm bón có ảnh hưởng đến khối lượng 1.000 hạt và số bông/khóm, còn liều lượng đạm làm tăng khối lượng chất khô tích lũy ở giai đoạn chín sáp khi tăng lượng đạm bón. Các giống lúa địa phương có số bông/khóm và tỉ lệ hạt chắc thấp nhất ở liều lượng đạm bón 45 kg N/ha, không có sự khác biệt ở hai liều lượng bón 68 kg N/ha và 90 kgN/ha. Trong khi đó, các giống cải tiến chịu mặn không bị ảnh hưởng bởi việc thay đổi liều lượng đạm bón, giống nhiễm mặn IR28 lại giảm về năng suất thực thu, số hạt/bông, tỉ lệ hạt chắc và khối lượng 1.000 hạt khi giảm lượng đạm bón từ 90 kg N/ha xuống 45 kg N/ha.
DOI: https://doi.org/10.31817/tckhnnvn.2017.15.3.
Causes of Farmers Who Abandon Star-Apple “Lo Ren” Productionwith Global GAP Standard in Chau Thanh District, Tien Giang Province

Tran Quoc Nhan, Nguyen Thi Hong Tham, Nguyen Thi Thuy Hang

Date Received: 20-07-2016 / Date Accepted: 16-09-2016 / Date Published: 13-06-2025
This study aimedto investigate thesocio-economic status offarm households growing star-apple “Lo Ren”according to Global GAP standard and clarifythe reasons for GAP adoption and abandonment after obtainingGlobal GAP standardcertification. A total of 54 star-apple growers who appliedGAP and 53 independent growers residing in Chau Thanh district of Tien Giang province were selected for primary data collection. Descriptive statitics and T-Test methods were employed to analyze the collected data related to GAP adoption and abandonment. Regardless of the benefits of GAP practices, such as reduced fertilizer and pesticide application and safety for environment, the abandon of GAP star apple growing was attributed to the uncertainty of market and unstable selling prices. Thus, only those farmers with higher education level, better economic condition and highexpectation for higher selling price of GAP-certified product engagedin growing star apple using GAP..
DOI: https://doi.org/10.31817/tckhnnvn.2016.14.9.
StudyonGreenhouse Gas Emission ofRice Soils in Thai Binh Province

Chu Sy Huan, Mai Van Trinh, Cao Viet Ha, Bui Thi Phuong Loan, Vu Thi Hang, Dinh Quang Hieu, Dao Thi Minh Trang, Bui Thi Thu Trang

Date Received: 04-12-2019 / Date Accepted: 11-03-2020
Objectives of research is to determine Greenhouse Gas (GHG) emission on rice field. Research was carried out on 3 soil types and 2 land use type: rice-rice and rice-rice-winter crop in 2018. Gas samples were taken 4 replications at each site, at 8 growing states and 2 rice season with total of 1024 sample by close chamber method and were analyzed by Gas Chromatograph. Research results showed that, CH4 emission in spring season increases from deriving new roots to tillering periods, then fluctuated depending on water level in the field. With acid sulphate soil, emission higher and in longer time. In summer, emission increase immediately after transplanting, get pick at periods of tillering - particle initiation (28mg CH4/m2/hr),then decrease gradually. N2O emission in spring season largely range in growing states and N fertilizer scheme and get pick at flowering time (0,4mg N2O/m2/hr). Total emission in terms of Global Warming Potential (GWP - ton CO2e /ha/year) ascending are the fluvisols of double cultivating rice season < saline soils < fluvisols cultivated 3 crops of double rice and upland crop <acid sulphate soils. Emission intensity (kgCO2e/kg rice grain) in the spring season in ascending are saline soils <double rice on fluvisols <3 crops of double rice and upland crop on fluvisols <acid sulphate soil.In summer season, double rice on fluvisols <saline soils <acid sulphate soils <3 crops of double rice and upland crop on fluvisols.
Methane Emission from Paddy Field Applied with Different Organic Matter Forms from Rice Straw

Nguyen Duc Hung, Nguyen Tho Hoang, Nguyen Huu Thanh

Date Received: 24-04-2018 / Date Accepted: 04-10-2018
This study was conducted to investigate CH4 emission as influenced by different organic matter forms from rice straw applied to paddy field (Eutric Fluvisols) planted with rice culivar Khang Dan 18 in the Spring and Summer seasons of 2015 and 2016. Keeping inorganic NPK level constant (100 kg N, 80 kg P2O5 and 80 kg K2O/ha), organic matter amendments included chopped rice straw (4500 kg/ha1), biochar produced from rice straw and compost (produced from 4500 kg rice straw). The emission rates of CH4 were measured by using the closed chamber method. Results showed that CH4 emission rates differed markedly with the forms of organic matter application. Pure application of mineral fertilizers yielded lowest CH4 emission rate but highest rice grain yield. In contrast, amendment with chopped rice-straw resulted in highest CH4 emission rate and lowest rice grain yield. Biochar and compost application lowered CH4 emission rate as compared with rice straw amendment. However, application of compost maintained rice yield comparable to mineral fertilizer.
Effect of Potassium Fertilizer Dosage on Growth and Yield ofJapanese Purple Sweet Potato (Ipomoea batatas Lam.) in Acid Sulphate Soils at Binh Tan District, Vinh Long Province

Le Thi Thanh Hien, Le Vinh Thuc, Truong Thi Minh Tam, Nguyen Bao Ve

Date Received: 03-11-2014 / Date Accepted: 04-06-2015
Potassium is an important nutrient for the growth and root yield of sweet potato. An experimentwas carried out to determine the optimal level of potassium for yield and quality of Japanese purple sweet potatoin acid sulfatesoils at Binh Tan District, Vinh Long Province. The experiment was set up in a randomized completed block design with 7 treatments and 3 replications, 35 m2/each replication (7 x 5 m). The treatments were 100 kg N/ha - 80 kg P2O5/ ha combined with 5 levels of K2O (0, 100, 150, 200 and 250 kg K2O/ha) and 80 kg P2O5/ha - 250 kg K2O/ha combined with 125 kg N/ha and 187 kg N/ha. The results showed that 200 kg K2O/ha combined with 100 kg N/ha - 80 kg P2O5/ha increased commercial rootyield of purple Japanese sweet potato by57.4% in comparisonwithzeroapplication of potassium or 31.2% compared with farmers' fertilizationpractice (100 kg K2O/ha). It was suggested thatgrowers should apply thisas recommendation for sweet potato cultivation in acid sulfatesoil at Binh Tan, Vinh Long.

1 - 23 of 23 items

Search

Advanced filters

Search Results