EFFECTS OF SEASONAL GRAFT ON B3 AVOCADOS IN NURSERY IN MAI SON DISTRICT, SON LA PROVINCE

Abstract

This stuydy was carried to find out the best time for grafting on B3 avocado variety at nursery garden in Son La. This study employed the tops grafting method for 7 arrangements of 150 potting plants / 1 arrangment. The experiment was set up in 7 arrangements. The findings showed that CT7 produced: slow germination time but the highest germination rate (91.63%). After 120 days of grafting, the cuttings were exceeding in both length and diameter compared to other arrangements in the experiment. The post-transplantation capacity of 120 days was higher, the conjugation index reaches 1.03. Prevalence of live germs reached 90.4%, the rate of plants out of the garden was 86.3%. In addition, the B3 avocado grafting formula in March, April and July also gave positive integration between rootstock and grafted branches, resulting in a higher rate of grafted plants ready for moving to gardens. The proportion of live transplanted trees reached 83.6% (March), 80.1% (April), 81.1% (July); The percentage of trees meeting garden export standards reached 75.6% (March), 73.1% (April), 71.2% (July). The study found that the most suitable grafting season for B3 avocado trees is spring-summer crop (March, 4), summer-autumn crop (July) and preferably winter crop (12th month).