Biochar Application and Shoot Cutting Duration (Days) Influenced Growth, Yield and Yield Contributing Parameters of Brassica Napus L

Abstract

Biochar is an organic amendment produced by a process called pyrolysis. Pyrolysis is the burning of biomass in a limited oxygen environment. In the recent past, agricultural use of biochar has been steadily increasing and attracting research interest. Biochar has been shown to reduce leaching of critical nutrients thereby providing greater soil availability and crop uptake. An experiment entitled “biochar application and shoot cutting duration influenced phenology and morphology rapeseed (Brassica napus L) was conducted at Agriculture Research farm Matta (Swat) during Rabi season 2012-13. The field experiment was carried out in randomized complete block design (RCBD) having four replications. The sub plot size was kept 5 m x 2.7 m having 6 rows with 0.45 m apart. Four levels of biochar (0, 5.0, 7.5 and 10 tons ha^-1) and five levels of shoot cutting duration after date of sowing (ADS), (no cutting, 30 days ADS, 40 days ADS, 50 days ADS and 60 days ADS) were used in the experiment with the test cultivar Dunkled. From the results it is observed that rapeseed cultivar positively responded for days to flowering, days to maturity, number of branches plant^-1, H.I %,  number of seeds pod^-1, thousand seed weight (g), biological yield (kg ha^-1), seed yield (kg ha^-1) and oil yield (kg ha^-1) to biochar levels and maximum seeds pod^-1 (23 seeds), thousand seed weight (3.59 g), biological yield (10310 kg ha^-1), seed yield (1169 kg ha^-1) and oil yield (600 kg ha^-1) was observed in plot treated with 10 ton biochar ha^-1. Whereas minimum seeds pod^-1 (15 seeds), thousand seed weight (2.41 g), biological yield (6725 kg ha^-1), seed yield (923 kg ha^-1) and oil yield (401 kg ha^-1) was recorded in control plot. Similarly highest seeds pod^-1(22), thousand seed weight (3.3 g), seed yield (1099 kg ha^-1) was noted in no shoot cutting plot followed by shoot cutting after 60 days of sowing ADS plots while promising biological yield (9025 kg ha^-1), and oil yield (568 kg ha^-1) was recorded in shoot cutting after 50 days ADS and after 60 days ADS of sowing. On the basis of the result it was concluded that shoot cutting with 10 ton biochar ha^-1 produced highest seed and oil yield with green chop and recommended for higher seed, oil and biological yield in the agro- climatic condition of swat valley.

Keywords: Rapeseed (Brassica napus L.), biochar, ADS, shoot cutting, yield, Oil, seeds pod^-1