STUDIES ON CRITICAL PERIOD OF CROP WEED COMPETITION IN HYBRID MAIZE
KrishiKosh
View Archive InfoField | Value | |
Title |
STUDIES ON CRITICAL PERIOD OF CROP WEED COMPETITION IN HYBRID MAIZE
|
|
Creator |
JITENDRA KUMAR SINGH
|
|
Contributor |
PRABHAKARA REDDY, G
|
|
Subject |
weeds, drying, maize, crops, grasses, yields, harvesting, sowing, biological competition, dry matter
|
|
Description |
Field experiment entitled “studies on critical period of crop weed competition in hybrid maize “was carried out during rabi 2009-2010 at wet land farm of S.V.Agricultural college, Tirupati, Andhra Pradesh. The experiment was conducted in a Randomized Block Design, replicated thrice with twelve treatments, viz; Weed free condition (WFC) up to 15, 30, 45, 60 and 75 DAS and weed interference (WI) up to 15, 30, 45, 60 and 75 DAS along with weed free and weedy check. The test cultivar was DHM 117. The density and dry weight of weeds tended to decrease with increasing weed free condition up to harvest. The lowest weed density and dry weight were registered with weed free check. Unweeed check resulted in highest density and dry weight of weeds. Growth parameters, viz., plant height, leaf area index and dry matter production, yield attributes, (cob girth, cob length, cob weight, number of grains cob-1 and test weight), grain yield and stover yield and harvest index of maize were significantly influenced by varying periods of weed free and weed interference conditions. Increasing trend with respect to plant height and dry matter production was noticed during the crop growing period up to harvest, while leaf area index increased up to 60 DAS, then declined towards harvest. The highest growth parameters were realized with weed free check, where as lowest growth parameters were recorded with weedy check. Plant height was non-significant at 20 DAS. Maximum dry matter production was noticed with weed free check, which was however on par with WFC up to 75 DAS. Yield components viz., cob girth, cob length, cob weight, number of grains cob-1 and test weight were higher with weed free check, which were however on par with WFC up to 75 DAS and WI up to 15 DAS. Significantly higher cob girth was recorded with weed free check. All the yield components suffered due to competition under weedy check. As regards to the grain yield and stover yield increasing trend was noticed with increase in weed free condition up to harvest. The highest grain yield was registered with weed free check, which was however on par with WFC up to 75 DAS and WI up to 15 DAS. While stover yield was significantly highest with weed free check. The lowest grain yield and stover yields were noticed in unweeded control. Significant deferences were found with respect to harvest index due to various weed free and weed interference treatments. The highest harvest index was recorded in weed free check, which was comparable with WFC up to 75, 60, 45 and 30 DAS and WI up to 15 or 30 DAS. Weedy check recorded the lowest harvest index, which was significantly lower than all other treatments. The highest gross returns were realized with weed free check, which were closely followed by WFC up to 75 DAS and WI up to 15 DAS. The net returns were highest with weed free check, which was on par with WFC up to 75 or 60DAS and WI up to 15 DAS. Weed free check recorded the highest B: C ratio, which was comparable with WFC up to 75 or 60 DAS and WI up to 15 or 30 DAS. Weedy check was resulted in lowest gross returns, net returns and B: C ratio which was significantly lower than all other treatments. In conclusion, it can be stated that the most critical period of crop weed competition in hybrid maize in alfisols of Southern Agro-climatic Zone of Andhra Pradesh was from 30 to 45 DAS. |
|
Date |
2016-06-04T13:42:54Z
2016-06-04T13:42:54Z 2010-07 |
|
Type |
Thesis
|
|
Identifier |
http://krishikosh.egranth.ac.in/handle/1/66773
|
|
Language |
en
|
|
Relation |
D8990;
|
|
Format |
application/pdf
|
|
Publisher |
ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY
|
|