Effect of different intercropping systems on soil moisture conservation, fruit yield and quality of Nagpur mandarin (Citrus reticulata) in central India

Abstract

A field experiment was conducted during 2009-2012 to study the integrated field crop based intercropping systems with cotton as main and other field crops (black gram, soyabean, groundnut, gram and mungbean)  as intermediate  intercrops in pre-bearing as well as bearing Nagpur mandarin orchards.  The treatment consisted of Nagpur mandarin + cotton, Nagpur mandarin + cotton + soyabean, Nagpur mandarin + cotton + blackgram, Nagpur mandarin + cotton + groundnut, Nagpur mandarin + soyabean followed by gram, Nagpur + black gram followed by gram, Nagpur mandarin + groundnut followed by summer mung and with no intercrop.  The plant canopy volume of Nagpur mandarin shown maximum increase of 28.81 m³ in Nagpur mandarin + soyabean followed by gram.  The highest Nagpur mandarin yield 20.0 t/ha (72.3 kg/tree) was recorded in the intercropping of Nagpur mandarin + soyabean followed by gram.  The pre-bearing orchard the Nagpur mandarin + black gram followed by gram was shown significant increase (10.66m³) followed by Nagpur mandarin + cotton + soyabean.  The total soluble solids (TSS) to acidity ratio was more in Nagpur mandarin + black gram followed by gram (15.95) and Nagpur mandarin + cotton + groundnut (14.51).  The fruit acidity and juice percent were also significantly affected. High soil moisture was observed in intercrops of soyabean and groundnut.  The maximum cotton yield was under treatment of intercropping   soyabean, black gram and groundnut compared to cotton alone. The number of pods per plants was more in soyabean grown with cotton (92.6) as compared to soyabean alone. This study reveled that the intercropping system with cotton + soyabean or cotton + black gram in the interspaces of pre-bearing and bearing mandarin improved the yield as well as sustainability of mandarin as well as the production of intercrops.