A field experiment was conducted to evaluate the bioefficacy of some potent low dose herbicides of sulfonylurea group in conjunction with other traditional recommended herbicides for control of broad spectrum of weeds in transplanted rice (Oryza sativa L) during the wet season of 2012 and 2013. Pretilachlor 750 g/ha as pre-emergence (PE) fb ethoxysulfuron 18.75 kg/ha as post-emergence or pretilachlor 750 g/ha followed by metsulfuron-methyl + chlorimuron-ethyl 4 g/ha or pyrazosulfuron 20 g/ ha (PE) followed by manual weeding were better options for efficient weed control, higher grain yield and B:C ratio in transplanted rice.

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A field experiment was conducted during Kharif, 2013 and 2014, Collage of Agriculture, Rajendranagar, Hyderabad in Telangana state. Fourteen weed management practices were evaluated in a randomized complete block design, replicated thrice. Significantly higher grain yield (6.9 t/ha) was obtained with either hand weeding twice at 25 and 45 DAT or pyrazosulfuron-ethyl 20 g/ha at 3 DAT followed by manual weeding at 25 DAT (6.8 t/ha) or pretilachlor 750 g/ha as pre-emergence (PE) at 3 DAT followed by metsulfuron-methyl + chlorimuron-ethyl 4 g/ha as post-emergence (PoE) at 25 DAT (6.6 t/ha) or bispyribac-sodium 20 g/ha + metsulfuron-methyl + chlorimuron-ethyl 4 g/ha as PoE at 25 DAT (6.3 t/ha). However, significantly higher net returns (`/ha) and B:C ratio were recorded with pyrazosulfuron-ethyl 20 g/ha at 3 DAT followed by manual weeding at 25 DAT of (` 69788, B:C 2.79), pretilachlor 750 g/ha as PE at 3 DAT followed by metsulfuron-methyl + chlorimuron-ethyl 4 g/ha as PoE at 25 DAT (` 67646, B:C 2.77), hand weeding twice at 25 and 45 DAT (` 68720, B:C 2.68), and bispyribac-sodium 20 g/ha + metsulfuron-methyl + chlorimuron-ethyl 4 g/ha as PoE at 25 DAT (` 62299, B:C 2.58).

Sweet sorghum (Sorghum bicolor (L.) Moench) is a potential bioenergy crop that produces both food (from grain) and biofuel (from stalk juice). The present investigation undertaken to assess the effect of different plant density and nitrogen levels on juice extraction and sugar quality traits of sweet sorghum grown in postrainy season of 2008-2009. Three planting geometries as main treatments (30 9 15, 45 9 15 and 60 9 15 cm) and four levels of nitrogen (0, 30, 60 and 90 kg ha -1 ) application levels as sub-plot treatments were assessed in split-plot design. It is found that the combination of relatively lower nitrogen application level (60 kg ha -1 ) with maximum population density (spacing 45 9 15 cm) are needed for higher sugar and ethanol yields in the farmer fields.

Rice plays a pivotal role in agrarian economy of the most of the Asian and South east Asian nations particularly India. Transplanted rice crop suffers much from biotic production constraints among which weed competition is the important one. The reduction in paddy yield ranges from 9-51 per cent due to infestation of wide range of weed species viz. grasses, sedges and broadleaved weeds. The severity of yield loss is aggravated further when weed infestation coincides with critical period of rice growth depriving it from moisture, nutrients, sunlight and acting as alternate host to some pests and diseases. The cost of weed management in transplanted rice is higher than other operations due to exorbitant wage rate combining with low efficiency moreover due to scarcity of labour during peak period, weeding operation has become a cumbersome, time consuming and costly affair for rice farmers. Therefore, herbicide technology offers a mutual inclusive method of selective and economical control of weeds right from the beginning and forms a major component of integrated weed management of rice farming for reaping bumper yield.