Modified water-nitrogen productivity function based on response of water sensitive index to nitrogen for hybrid maize under drip fertigation

2021 ◽  
Vol 245 ◽  
pp. 106566
Author(s):  
Yufeng Wang ◽  
Shaozhong Kang ◽  
Fusheng Li ◽  
Xiaotao Zhang
1989 ◽  
Vol 28 (03) ◽  
pp. 100-104 ◽  
Author(s):  
S. F. Akber

The first-pass pulmonary extraction values of N-lsopropyl-123l-p-lodoamphetamine (123I-IMP) in pretreated dogs decreases from 90 to 62% as the amount of propranolol increases from 0 to 20 mg. The first-pass pulmonary extraction values of 123I-IMP in dogs with a simultaneous bolus injection of propranolol decreases from 90 to 62% as the amount of propranolol increases from 0 to 10 mg. The pulmonary extraction of 123I-IMP with a simultaneous bolus injection of ketamine and 123I-IMP decreases from 90 to 64% as the ketamine dose increases from 0 to 100 mg. These results suggest that the pulmonary uptake of 123I-IMP may be at least partially mediated by receptors. They also indicate that endothelial metabolic cell function may be a useful index of early lung pathology. Furthermore, studies of the degree of lung uptake may be a sensitive index of pathologic states in which alterations of amine binding sites have occurred.


2006 ◽  
Vol 54 (3) ◽  
pp. 343-350 ◽  
Author(s):  
C. F. H. Longin ◽  
H. F. Utz ◽  
A. E. Melchinger ◽  
J.C. Reif

The optimum allocation of breeding resources is crucial for the efficiency of breeding programmes. The objectives were to (i) compare selection gain ΔGk for finite and infinite sample sizes, (ii) compare ΔGk and the probability of identifying superior hybrids (Pk), and (iii) determine the optimum allocation of the number of hybrids and test locations in hybrid maize breeding using doubled haploids. Infinite compared to finite sample sizes led to almost identical optimum allocation of test resources, but to an inflation of ΔGk. This inflation decreased as the budget and the number of finally selected hybrids increased. A reasonable Pk was reached for hybrids belonging to the q = 1% best of the population. The optimum allocations for Pk(q) and ΔGkwere similar, indicating that Pk(q) is promising for optimizing breeding programmes.


2017 ◽  
Vol 10 (02) ◽  
pp. 212-220
Author(s):  
Jeyajothi R ◽  
◽  
Kandeshwari M ◽  
Pandiselvi T ◽  
Keyword(s):  

Author(s):  
Norhanishah Mohamad Yunus ◽  
Noraida Abdul Wahob

A plethora of studies have revealed the importance of new knowledge transfer from foreign multinational corporations (MNCs) in encouraging higher labour productivity and sustainable competitive advantages. However, less attention is given to low labour productivity issue despite the presence of FDI, especially in the developing country context. Most of the studies only heavily emphasised on 'technology' effects rather than 'knowledge' effects on the host country as a result of the presence of foreign technology. As Malaysia is one of the major FDI recipients in Southeast Asia, the specific spillover effects of each FDI investor country in Malaysia, need to be studied. With an abundance of MNCs, international technology transfer is considered as an imported mode for technology acquisition in a developing country like Malaysia. However, the benefits of FDI spillovers on labour productivity function in Malaysia remain ambiguous, even when classified according to specific investor countries. Globalisation and liberalisation have seen trade and investment activities booming, thus increasing multilateral relations between Malaysia and other countries regardless of their level of development. Thus, this study may help the Malaysian government to justify the cost that should be invested to attract more FDI inflows towards the manufacturing industries in the short run. Keywords: spillover effects, Foreign Direct Investment, labour productivity, technology spillovers, knowledge spillovers


2017 ◽  
Vol 4 (03) ◽  
Author(s):  
SAMBORLANG K. WANNIANG ◽  
A. K. SINGH

A field experiment was conducted during kharif 2011 on experimental farm of the College of Post Graduate Studies (CAU–Imphal), Umiam (Meghalaya) to evaluate the effect of integration of green manuring, FYM and fertilizers as integrated nutrient management (INM) practices on growth and developmental behaviour of quality protein maize cultivar QPM 1. The data revealed that comparatively higher amount of primary nutrients were added in green manured maize plots in comparison to non green manured treatments. Green manuring also left a positive response on plant height, CGR, RGR leaf area, and dry matter accumulation in plants though the difference between green manured and non-green manured treatments was at par. Treatments 75 % RDF + 5 t FYM ha-1, 50 % RDF + 7.5 t FYM ha-1, 100 % RDF ha-1 and 75 % RDF + 2.5 t FYM ha-1 recorded significantly higher values of all the above said growth parameters over 50 % RDF + 5 t FYM ha-1 and control treatments. At all stages of observations, the maximum dry matter was associated with RDF (recommended doses of fertilizers) which was at par with 75 % RDF + 5 t FYM ha-1, but significantly higher over the plant dry weight recorded from all remaining treatments. A Significant difference in CGR at 30 – 60 and 60 – 90 DAS stage and in RGR at 90 DAS - harvest stage was observed due to various combinations of recommended dose of fertilizer with different doses of FYM. Number of days taken to attain the stages of 50% tasselling, silking and maturity did not differ significantly due to green manuring. However, treatment 75 % RDF + 5 t FYM ha-1 took significantly lesser number of days for these stages than other treatment combinations. The superiority of the treatment 75 % RDF + 5 t FYM ha-1 indicated a possibility of substituting 25% of RDF with 5 t FYM ha-1 without any loss in dry matter accumulation in plants of the quality protein hybrid maize in mid-hill ecosystems of Meghalaya.


Genetics ◽  
2018 ◽  
Vol 210 (3) ◽  
pp. 1125-1138 ◽  
Author(s):  
Joseph L. Gage ◽  
Michael R. White ◽  
Jode W. Edwards ◽  
Shawn Kaeppler ◽  
Natalia de Leon

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2019
Author(s):  
Sukanta K. Sarangi ◽  
Sudhanshu Singh ◽  
Ashish K. Srivastava ◽  
Madhu Choudhary ◽  
Uttam K. Mandal ◽  
...  

This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the land remains fallow during the dry season because of increased salinity and scarcity of freshwater for irrigation. The study aims to provide options for increasing cropping intensity through management of crop residues (CR) and soil salinity, conservation of soil moisture, and reduction in production cost. The rice–maize rotation was assessed with rice as the main plot as (1) puddled transplanted rice (PTR) with CR of both rice and maize removed, (2) PTR and 40% CR of both crops retained, (3) dry direct-seeded rice (DSR) with CR of both crops removed, and (4) DSR with 40% CR of both crops retained. Maize in the dry season was supplied with different N levels as sub-plots—control (0 kg N ha−1), 80, 120, and 160 kg N ha−1. DSR, when combined with CR retention (DSR + R), reduced soil salinity. The increase in rice grain yield with CR retention (observed in second and third years) and crop establishment (higher in DSR versus PTR in the third year) was 16 and 24%, respectively. The cost of production increased by 17% (USD 605 ha−1) in PTR compared with DSR (USD 518 ha−1). CR retention reduced irrigation water requirement by 37% and N requirement by 40 kg ha−1 for hybrid maize. When CR was removed (−R), the N requirement for hybrid maize increased to 160 kg N ha−1 compared to when it was partially (40%) retained, where the requirement was 120 kg ha−1 with similar yields. Available N was highest under DSR + R (314 kg ha−1) and lowest under PTR − R (169 kg ha−1), and it also increased with increasing N application up to 120 kg ha−1 (+R) and 160 kg ha−1 (−R). The results of the study hold promise for increasing cropping intensity and farmers’ incomes, with broader implications for increasing productivity on about 2.95 million hectares currently under a rice–fallow system in eastern India, and in coastal areas affected by similar conditions in South and Southeast Asia.


Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 934
Author(s):  
Roman Rolbiecki ◽  
Stanisław Rolbiecki ◽  
Anna Figas ◽  
Barbara Jagosz ◽  
Dorota Wichrowska ◽  
...  

Most species of Cucurbitaceae respond favorably to irrigation, especially when combined with fertilizers. The effect of drip irrigation combined with nitrogen fertigation in melon grown on a very light soil in Central Poland, during 2013–2015, was evaluated. The field experimental design was a split-plot with four replications. Two factors were studied: (1) irrigation treatments applied in two combinations—drip irrigation + broadcast nitrogen fertilization (control), and drip irrigation + fertigation with nitrogen; (2) two cultivars—Melba and Seledyn. The total marketable yield of fruits, weight of a single fruit, and the concentration of dry matter, total sugars, monosaccharides, ascorbic acid, total carotenoids, and polyphenols were evaluated. Tested factors presented a significant effect both on the yield and nutritive value characteristics. Drip irrigation combined with nitrogen fertigation, comparing to the control, notably improved yields and nutritional value of fruits. Seledyn produced better yields than Melba. This study shows that on very light soil, with low water and nutrient retention capacity, melon should be drip-irrigated and nitrogen-fertigated to obtain the best cultivation results.


Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 330
Author(s):  
Jean-Christophe Castella ◽  
Sonnasack Phaipasith

Road expansion has played a prominent role in the agrarian transition that marked the integration of swidden-based farming systems into the market economy in Southeast Asia. Rural roads deeply altered the landscape and livelihood structures by allowing the penetration of boom crops such as hybrid maize in remote territories. In this article, we investigate the impact of rural road developments on livelihoods in northern Laos through a longitudinal study conducted over a period of 15 years in a forest frontier. We studied adaptive management strategies of local stakeholders through the combination of individual surveys, focus group discussions, participatory mapping and remote-sensing approaches. The study revealed the short-term benefits of the maize feeder roads on poverty alleviation and rural development, but also the negative long-term effects on agroecosystem health and agricultural productivity related to unsustainable land use. Lessons learnt about the mechanisms of agricultural intensification helped understanding the constraints faced by external interventions promoting sustainable land management practices. When negotiated by local communities for their own interest, roads may provide livelihood-enhancing opportunities through access to external resources, rather than undermining them.


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