Abstract:
An experiment involving eight treatments replicated three times in a randomized complete block design was established at Chitedze Agricultural Research Station ( 13o 59, 23.2" S, 033o 38' 36.8" E) in the 2012/2012 cropping season in order to assess nutrient uptake and yields for the crops in a legume-cereal rotation cropping system. Two pigeon pea varieties, long (ICEAP 04000) and medium duration (ICEAP 00557) and groundnut (CG 7) were grown as monocultures and intercrops. The intercrops involved planting either of the pigeon pea varieties with groundnut. At harvest time legume biomass was buried into the soil and each plot split into four subplots to accomodate four different levels of N (0, 50, 100, 150 kg N ha-1) were applied at top dressing to the succeeding maize crop in the 2012/2013 cropping season. During planting, in the 2012/2013 cropping season the maize crop was basal dressed with 50 kg P ha-1. Top dressing with N was conducted three weeks after emergence. For groundnut, results from statistical analysis indicated non significant differences ( p>0.05) in the yields of grain. The grain yields ranged from 1,513 to 3,025 kg ha-1. N concentration in the grain ranged from 2.9% to 3.2% translating into N yields that ranged from 46.9 kg N ha-1 to 98.8 kg N ha-1. The N yields for grain were higher than N yields for the shells and haulms. The concentration of N in the maize grain ranged from 1.1% to 2.1%, while maize grain yields ranged from 1,775 to 5, 806 kg ha-1 and the N yields ranged from 23 to 115 kg N ha-1. This was higher than N yields for stover and rachids. The data indicated that more N in the groundnut and maize plant is translocated to the grain as such there is net export of N from the field. |
