Growth and Development of Low Seeded Kinnow Mandarin Fruits in Dense Plantation

The work described here is unique since the low seeded (0-6 seeds per fruit) Kinnow (Citrus reticulata) germplasm was grown in dense plantation (P P: 1foot and L L: 2 feet) in the NIAB (Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan) field. Growth and development patterns of the fruits were studied. The low seeded germplasm contains 3,500 plants developed through natural and induced variability in Kinnow mandarin. The area is surrounded by other cross compatible Citrus varieties. The germplasm flower was hermaphrodite, off-white, the color of the anthers yellow, and the number of petals was five and all other flower characteristics were variable. In 2005 the fruiting was in 596 plants and the maximum fruit range was 21-40 in 99 plants followed by 41 to 75 in 98 plants. In 2006, 322 plants bore fruit and 1-5 fruits per plant were found in 93 plants followed by 6-10 fruits per plant in 61 plants. In 2007, 551 plants had first time bearing and the maximum fruit range per plant was 11-20 in 116 plants followed by 21-30 in 99 plants. It was found that the Kinnow fruit gains maximum weight during August-October whilst the volume of the fruit increases during August-November. Initially the height and diameter were identical in May giving the fruit a round shape and then the gradual increase in height slowed down, resulting in an oblate to subglobose shape of the fruit. In mid-January the average fruit weight was 192 grams and the average peel weight was 45 grams. Peel thickness was more at stalk end as compared to stylar end. All low seeded fruits had their navel at the stylar opening point. The maximum number of fruits had 11 segments but the segment range was 9-14 per fruit. In mid-January the juice pH, juice acidity and TSS had variable values in plants indicating variation in the fruit physiological maturity time within the germplasm. The growth of fruits was similar to that reported in low density orchards