SRINIVASULU REDDY, DSAMPATH KUMAR, DADIGIRI2020-11-242020-11-242003https://krishikosh.egranth.ac.in/handle/1/5810155690D1215 - DADIGIRI SAMPATH KUMARA study on "rop intensification in rainfed alfisols" was takenup at Agricultural Research Station (ANGRAU), Kadiri (Scarce rainfall zone of Andhra Pradesh), through two experiments, simultaneously for two consecutive years during 2000 and 2001, one with the aim of establishing an efficient groundnut based intercropping system and another to study the possibility and identifying efficient groundnut based sequence cropping system for enhancing the crobping intensity to the extent as maximum as possible in rainfed alfisols. I. \ In the first experiment, groundnut sbwn at 30 cm spacing was intercropped with pigeonpea, castor, sorghum, pearlmillet, sunflower, sesame, greengram and soybean at 7:1, 7:1, 6:2, 6:2, 3:1, 3:1, 3:l and 3:l row proportions, respectively. All the treatments were tried in additive series version of intercropping, keeping the population of base crop (groundnut) in all the treatments at 100 per cent of its sole crop (3, 33, 333 plants ha"), by adjusting the intra-row spacing. In second experiment, groundnut was grown during kharifin all treatments and immediately after harvesting of groundnut, seven shd duration crops viz., greengram, cowpea, sunflower, horsegram, clusterbean, pearlmillet and sorghum were raised in each treatment during rabi. Both the experiments were conducted in randomized block design and replicated thrice, Intercropping of groundnut with pearlmillet or sorghum registered the highest plant height of groundnut, during both the years of study. Groundnut + pigeonpea system resulted in the shortest groundnut plants. Number of leaves per plant, LAI, dry matter production (kg ha- ) and number of root nodules per plant of groundnut were higher with pigeonpea as intercrop, closely followed by intercropping with castor. All these growth parameters were at their lowest with pearlmillet and sorghum as intercrops. Yield attributes of groundnut viz., number of branches, flowers, pegs, total and filled pods per plant; hundred pod weight, hundred kernel weight, I shelling percentage and sound.mature kernel percentage of groundnut were found to be the highest with gi-oundnut + pigeonpea intercropping system, which were however, co6arable with groundnut + castor system. All these attributes were at their lowest, when groundnut was intercropped with either 4' pearlmillet or sorghu,p. I Pod yield (pooled mean) of groundnut was the highest with groundnut. + pigeonpea, which was on par with groundnut + castor. The lowest pod yield of groundnut was realized with pearlmillet or sorghum as intercrops. Haulm yield of groundnut hllowed the same trend of pod yield. Groundnut pod equivalent yield (pooled mean) of intercropping system was the highest with groundnut + castor, which was coinpirable with groundnut + ..pigeonpea. Groundnut + soybean system recorded the lowest groundnut pod equivalent yield, which was significantly inferior to other intercropping systems, except with groundnut + greengram. Efficiency evaluation indices viz., LER, ATER and SLER were found to be maximum with groundnut + castor followed by groundnut + pigeonpea, while groundnut intercropped with greengram resulted in the ,lowest values of these indices. The net gain of soil available nitrogen was the highest with groundnut -k pigeonpea system, while the lowest net gain was associated with groundnut + sorghum. The highest and lowest net gain of soil available P2O5 was recorded with groundnut + pearlmillet and groundnut + sesame intercropping systeins, respectively. The net gain of soil available K20 was the highest with groundnut + soybean system, while the lowest net gain was associated with groundnut + sorghum intercropping system. Net returns and benefit cost ratio were the highest with groundnut + castor system, which were comparable with groundnut + pigeonpea, while the lowest net returns and benefit cost ratio were registered with groundnut + soybean. The highest monetary advantage was realised with groundnut + castor intercropping system, which was significantly superior to all other + intercropping systems, while ihi lowest was associated with grounclnut + greengram system. The highest dry matter production, econoinic yield (groundnut pod equivalent yield) and the econon~ic returns of different sequence crops tried after 1cl.larif groundnut was maximum with clusterbean, which were significantly superior to rest of the crops, while sorghum as the sequence crop recorded all the above parameters at their lowest level, with negative net returns.EnglishThesis