Evaluation of clusterbean (Cyamopsis tetragonoloba) intercrop in agri-silviculture system in south-western Punjab

An experiment was conducted during the rainy season of 2016 and 2017 at Bathinda, Punjab, to check the intercropping feasibility of guar or clusterbean (Cyamposis tetragonoloba (L.) Taub] under an agri-silvicultural model comprising 2 year-old plantation of eucalyptus (Eucalyptus tereticornis Sm.), poplar (Populus deltoids Bartr. Ex Marsh.) and Malabar neem or dek (Melia dubia Cav.; syn. M. composita Willd.) at the spacing of 7 m x 3 m. Clusterbean was also sown as sole crop in open space as the control. During the first year of study, plant growth attributes of clusterbean like plant height and days taken to 50% flowering were non-significant. Although the trend was similar in 2nd year, treatment combination under tree canopies took more days (1–2 days) to attain 50% flowering and maturity. There was increase (7–10%) in tree height (1.27, 0.65 and 1.24 m), girth (1.70, 1.20 and 1.45 mm) and canopy cover (0.29, 0.47 and 0.36 m) in all the 3 tree species of eucalyptus, dek and poplar, respectively, which prolonged the days to attain flowering and maturity of the crop grown under the plantation crop. Number of branches (3.33 and 3.20) were more in sole crop in comparison to treatment combination during both the years. Number of pods and number of seeds/pod were at par in 1st year, while differences were significant in the next year. Seed yield (1.06 and 1.05 t/ha) was significantly higher in sole system during both the years, but the differences were more wider in later year. Thus, sole crop gave highest seed yield but agri-silvicultural model with legumes as intercrop will provide opportunities to diversify as well as increase overall land productivity than individual systems.