A. Srinivas

Weed management through early post-emergence herbicides to improve productivity and nutrient uptake in greengram

A field experiment was conducted at College of Agriculture, PJTSAU, Rajendranagar, Hyderabad (Telangana) during rainy season 2015–16 on sandy loam soil to study the weed growth, yield and nutrient uptake in greengram under different early post-emergence herbicide treatments. Lower density and dry matter of weeds was recorded with hand weeding at 20 and 40 DAS followed by haloxyfop-p-methyl 135 g/ha + imazethapyr 75 g/ha at 12–15 DAS as early post-emergence, which remained at par with quizalofop-ethyl 50 g/ha + imazethapyr 75 g/ha at 12–15 DAS. Hand weeding twice at 20 and 40 DAS showed the highest uptake of N, P and K, which was comparable with haloxyfop-p-methyl 135 g/ha + imazethapyr 75 g/ha at 12–15 DAS and quizalofop-ethyl 50 g/ha + imazethapyr 75 g/ha at 12–15 DAS. Significantly higher seed yield was observed with hand weeding at 20 and 40 DAS (1.09 t/ha) which remained at par with haloxyfop-p-methyl 135 g/ha + imazethapyr 75 g/ha at 12–15 DAS (1.03 t/ha) and quizalofop-ethyl 50 g/ha + imazethapyr 75 g/ha at 12–15 DAS (1.01 t/ha).

Productivity and Economics of Rice (Oryza sativa)-Zero Till Maize (Zea mays) as Affected by Rice Establishment Methods and Weed Management Practices

Rice (Oryza sativa L.) – rice is the predominant cropping sequence in Andhra Pradesh. Rice is grown mostly under transplanting method in India, though transplanting is popular and successful method the fact is that it is labour intensive practice. The inadequacy of irrigation water and scarce labour coupled with higher wages during the peak period of farm operations, invariably lead to delay in transplanting. To overcome this problem, farmers are gradually switching over to maize crop production in the rabi season. Replacement of rice with maize (Zea mays L.) in dry season is increasing to save water and for maximum system production. Weed management is an important key factor in obtaining higher crop yield. Unchecked weed growth causes a International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 10 (2017) pp. 945-952 Journal homepage: http://www.ijcmas.com

Nodulation, Leghaemoglobin Content and Yield of Greengram as Influenced by New Generation Early Post Emergence Herbicide Combinations

Greengram is the third important pulse crop of India in terms of area 3.77 millon ha and production 1.52 million tonnes (DAC, 2015). It serves as a vital source of vegetable protein (19.1–28.3 %) and vitamins (Singh et al., 2015). Weed infestation is one of the major constraints in greengram cultivation and causes 50 to 90 % yield loss (Kumar et al., 2006). Being a short statured crop it is invaded by a large number of fast growing weeds at initial stage. Hand weeding is effective in controlling the weeds but unavailability of labor and continuous rainfall in rainy season does not permit it to operate timely. It is also time consuming and costly. Therefore, chemical control of weed forms an excellent alternative to manual as well as mechanical weeding and provides weed-free environment from emergence up to 30–35 days (Dungarwal et al., 2003). However, the adverse impact of herbicides on nodulation in legumes was reported (Ahemad, 2012).

Modeling of Soil-Plant-Fertilizer Relationships for Optimizing Fertilizer Doses for Different Levels of Finger Millet Yield under Semi-Arid Alfisols

ABSTRACT Experiments were conducted to test the superiority of treatment combinations of nitrogen (N; 0, 50, 100, 150, 200 kg ha−1), phosphorus (0, 30, 60, 90 kg ha−1) and potassium (0, 30, 60 kg ha−1) for finger millet during 2005–2007. Application of 200-90-60 kg ha−1 gave maximum yield of 1666, 1426 and 1640 kg ha−1 in 3 years, respectively. The yield regression model through soil and fertilizer nutrients gave predictability of 0.98, 0.97 and 0.98, with sustainability yield index (SYI) of 50.4, 49.4 and 52.5 in 2005, 2006 and 2007, respectively. Optimum nitrogen, phosphorus and potassium (NPK) doses for attaining yields of 800 and 1200 kg ha−1 were derived at soil nitrogen, phosphorus and potassium of 75–400, 10–70 and 150–750 kg ha−1. Fertilizer nitrogen, phosphorus and potassium ranged from 30–128, 3–19, 13–25 kg ha−1 and 105–203, 4–32, 27–39 kg ha−1 for attaining 800 and 1200 kg ha−1 yield, respectively. The doses could be adopted for attaining sustainable yields under semiarid Alfisols.