Influence of Different Colony Placement Distances on Yield and Quality Parameters of Peach (Prunus persica L.)

Optimum pollination requirement of peach (Prunus persica L.) cultivar 'Flordasun' by placing Apis mellifera L. colony at different distances from the plants was evaluated vis-a-vis their effect on quantitative and qualitative yield parameters at RRS, Karnal. A. mellifera foragers were maximum (36.6 9 bees/㎡) at closest distances of 20m followed by 40m (30.9) and dwindled drastically to half (18.2) with the increase in distance to 70m and further (59.8%) at the farthest distance of 100m (14.7/㎡). A positive and significant correlation was observed between colony distance, pollinator's population and yield parameters. At the closest distance (20m), the fruit set was the maximum (6.5 fruits/branch), decreased marginally (6.1 fruits) at 40m and greatly at 70 and 100m (3.3 and 2.7 fruits/branch, respectively). The caged plants (without insect pollination) bore least number of fruits (1.6/branch) with lowest yields and 35.7percent branches had no fruit set at all. Whereas, at all the four distances evaluated, yield parameters significantly and overwhelmingly out-performed WIP treatment and had no barren branches. Fruit yield (per branch) was maximum at 20m (343g) followed by 40m (301.3g) with a marked reduction at 70 (141.3) and 100m (115.3g). At closer distance, the mean fruit weight was almost equal (51.1 and 49.4g) and was significantly lower (42.8 and 42.7g) at the farther distances but comparable to WIP (42.6g). At 100m, fruit yield was minimum (94.60q/ha) and increased to 104.18q at 70m (an increase of 110.1%). At 40m, the yields increased substantially to 240.90q (by 254.7%) and were maximum (259.33q/ha) at the closest distance of 20m (increase of 274.1%). Compared to WIP that has lowest yield of 49.78q/ha, increase in yield was 190.0% at 100m, 209.3% at 70m, a significant 483.9% at a still closer distance of 40m and a whooping 521.0% at the closest distance of 20m. Fruits of bigger size (4.0×4.6cm length) were harvested at closer distance and their length decreased by 6.5~8.7% at farther distance. However differences in breadth and TSS (%) were non-significant at different distances. Total economic gains were highest at 20m (Rs. 1,52,598/ha) and 40m (Rs. 1,41,540) and were only Rs. 59,508 and 53,760 at 70 and 100m whereas Rs. 29,868 in WIP. Placing colonies nearer the crop from 100 to 70m resulted in an additional income of Rs. 5,748. This increment was Rs. 57,912 at 40m and an astonishing Rs. 98,838/ha at 20m distance. Based on the effective area coverage by the bees, 2 colonies/ha (10-frame) optimally pollinated the peach but they shall be placed not farther than 40m from the orchard.