Optimum sowing date and nitrogen fertilizer rate for rice varieties under intermediate deepwater conditions (15–50 cm)

1992 ◽  
Vol 118 (2) ◽  
pp. 179-183 ◽  
Author(s):  
A. R. Sharma ◽  
M. D. Reddy

SUMMARYIn an intermediate deepwater situation (15–50 cm) at Cuttack, India, three improved high-yielding rice varieties, Utkalprabha (semi-tall), CR 292–8051 (intermediate tall) and Gayatri (semi-dwarf) were sown on 20 May, 30 May and 10 June in 1988 and 1989 with an application of either 0, 20 or 40 kg N/ha at sowing. Tall varieties performed better than the dwarf type but grain yield decreased with delay in sowing. The early-sown crops (20–30 May) germinated with pre-monsoon rains and were established well before water accumulated in the field from mid-June onwards. The late-sown crops (10 June), despite good initial germination, could not withstand immediate waterlogging. The tall variety, Utkalprabha, elongated faster with rising water level and escaped complete submergence; whereas the semi-dwarf Gayatri failed to withstand such extreme excess water stress. Application of N fertilizer up to 40 kg/ha proved beneficial to the crops sown by the end of May. However, with crops sown on 10 June, the application of N could not compensate for the loss in yield due to an inadequate initial crop stand. Therefore, early sowing of tall varieties by the end of May along with a basal application of N fertilizer is recommended for higher productivity of rice under excess water conditions.

1991 ◽  
Vol 27 (1) ◽  
pp. 79-85 ◽  
Author(s):  
M. D. Reddy ◽  
A. R. Sharma ◽  
M. M. Panda

SUMMARYTwo early maturing semi-tall (120–130 cm) rice varieties, Kalinga-3 (85 days duration) and Banaprabha (95 days duration), were compared in pure and mixed crop stands under intermediate deepwater conditions (15–50 cm) with a modern late maturing (170 days duration) semi-dwarf (100 cm) variety, CR 1016. Parallel line seeding of CR 1016 and Kalinga-3 or Banaprabha in alternate rows (1:1 ratio) 20 cm apart yielded 19% more grain than a pure crop of CR 1016 alone. Mixed crop planting in a 1:2 or 2:1 ratio or with reduced inter-rovv spacing gave no additional yield advantage. Mixed row cropping prevented lodging in early varieties, whereas monocrops of the same varieties were partially lodged and showed some premature seed germination. The better and more stable yields obtained from such mixed cropping could be beneficial to resource poor farmers growing rice in conditions of excess water.


1995 ◽  
Vol 43 (4) ◽  
pp. 391-408
Author(s):  
A.B. Smit ◽  
P.C. Struik ◽  
J.H. Van Niejenhuis

PIEteR, a field-specific production model for sugarbeet in the Netherlands, is described. The model was developed as a basis for decision support, for example in determining N fertilizer requirements. Root and sugar yields, sugar content, (K + Na) and alpha -amino-N contents, extractability index, operating receipts (a measure for financial returns) and residual nitrogen in leaves are modelled as function of N availability, defined as (N-fertilizer rate + Nmin, 0-60 cm (soil, February)), and included in PIEteR as a so-called 'N-module'. Analysis of experimental data showed that root and sugar yield were optimal at 240 and 200 kg N ha-1, respectively. Sugar content and extractability index decreased, and (K + Na) and alpha -amino-N contents and fresh leaf yield increased with increasing N-availability. The operating receipts were optimal with 180 kg ha-1, or with a nitrogen fertilizer rate of 130 kg ha-1, assuming an Nmin-amount in soil in February of 50 kg ha-1. The results of the analysis were the basis for the functions in the N-module. In an independent test on data of 100 fields, the prediction errors for root and sugar yields and financial results decreased by about 2% and the explained variances increased by about 15% by including the N-module.


Author(s):  
Faridah Manaf ◽  
Roslan Ismail ◽  
Arina Shairah Abdul Sukor

Reducing nitrogen (N) fertilizer rate have beneficial effect on N uptake by plants. Studies on reducing N rate in sweet potato and beetroot to improve their growth and yield are well documented but the effect of decreased N rate on N uptake by leafy vegetables are limited. A glasshouse experiment was conducted to determine the effect of different N rate on N uptake of green spinach. Treatments evaluated were (i) soil alone, and (ii) different N fertilizer rate (12, 24, 36, 60, 90 and 120 kg N/ha). Treatments were applied at 14 days after seeding (DAS) at a uniform rate of 2 t/ha. Results revealed that moderate N input between 12 to 36 kg N/ha improved N uptake and yield of spinach compared with lower rate of N input (0 to 12 kg N/ha) but higher N level of 90 kg N/ha was most effective in improving N uptake and fresh yield. The effectiveness of N input at 90 kg N/ha corresponded to the optimum retention of soil N resulting in timely availability of N for uptake by spinach leading to higher yield. Although treatment with excess N (120 kg N/ha) improved N uptake, the decline in yield was because of soil nutrient imbalance that inhibited other nutrients required by plants for growth and development. The findings from the study suggest that reducing N fertilizer rate improves N uptake in leafy vegetables without reducing productivity depending on their specific N requirement.


2019 ◽  
Vol 5 (1) ◽  
pp. 1707020
Author(s):  
Amare Aleminew ◽  
Getachew Alemayehu ◽  
Enyew Adgo ◽  
Tilahun Tadesse ◽  
Manuel Tejada Moral

2014 ◽  
Vol 94 (2) ◽  
pp. 425-432 ◽  
Author(s):  
R. E. Karamanos ◽  
K. Hanson ◽  
F. C. Stevenson

Karamanos, R., Hanson, K. and Stevenson, F. C. 2014. Nitrogen form, time and rate of application, and nitrification inhibitor effects on crop production. Can. J. Plant Sci. 94: 425–432. Nitrogen management options for anhydrous ammonia (NH3) and urea were compared in a barley–wheat–canola–wheat cropping sequence (2007–2010) at Watrous and Lake Lenore, SK. The treatment design included a factorial arrangement of N fertilizer form (NH3versus urea), nitrification inhibitor application, time of N application (mid-September, mid- to late October, and spring) and four N fertilizer rates (0, 40, 80 and 120 kg ha−1). Anhydrous ammonia applications at 40 kg N ha−1in 2008 (fall) and in 2010 (all times of application) resulted in wheat yield reductions relative to the same applications for urea. For wheat years, yield was reduced for both fall versus spring N fertilizer applications, when no nitrification inhibitor was applied and the inclusion of nitrification inhibitor maintained wheat yield at similar levels across all times of N fertilizer applications, regardless of form. Protein concentration was approximately 2 g kg−1greater with urea compared with NH3at both sites in 2008 and only at Watrous in 2010. Also, early versus late fall N fertilizer applications consistently increased N concentration of grain only for the 40 and/or 80 kg N ha−1rates. Effects of nitrification inhibitor on N concentration were not frequent and appeared to be minimal. Urea had greater agronomic efficiency (AE) than NH3at the lower N fertilizer rates. The nitrification inhibitor had a positive effect on wheat AE only for early fall N fertilizer applications. It can be concluded that for maximum yields NH3or urea will be suitable if applied at rates of 80 kg N ha−1and greater. If N fertilizer is applied at 40 kg N ha−1, especially in fall without inhibitor, urea is better. In terms of protein concentration for wheat, urea seemed to better than NH3and fall was better than spring application.


2018 ◽  
Vol 43 (3) ◽  
pp. 243-260
Author(s):  
Nurudeen Abdul Rahman ◽  
Asamoah Larbi ◽  
Andrews Opoku ◽  
Francis Marthy Tetteh ◽  
Irmgard Hoeschle-Zeledon

cftm ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 1-9
Author(s):  
David D. Tarkalson ◽  
David L. Bjorneberg ◽  
Rick D. Lentz

Agric ◽  
2021 ◽  
Vol 33 (1) ◽  
pp. 57-66
Author(s):  
Kiki Kusyaeri Hamdani ◽  
Yati Haryati

New superior varieties (VUB) are a reliable technological innovation to increase rice productivity. This study aims to determine the yield potential of some lowland rice VUB. The assessment was carried out on land owned by a member of the Sumber Rejeki Farmer Group, Cintaratu Village, Lakbok District, Ciamis Regency at Dry Season II in June-September 2020. The study used a randomized complete block design (RCBD) with six varieties of treatment and was repeated ten times. The varieties tested were Inpari 32, Inpari 42, Padjadjaran, Cakrabuana, Inpari IR Nutrizinc, and Siliwangi varieties. The variables observed included the growth component, yield component, and yield component. Data were analyzed using the F test followedby the Duncan Multiple Range Test at the Q=5% level. In addition, a correlation test was conducted between the growth components, yield components, and yields. The results of the study indicated that the new superior rice varieties studied had different performance in growth, number of tillers, yield, and yield components. Inpari 42 variety produced the highest productivity, namely 6.88 ton ha-1 which was supported by the number of grains per panicle, percentage of filled grains per panicle, and percentage of empty grain per panicle which were better than other varieties. Plant height and number of grains per panicle were positively correlated with yield.


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