Pollination for custard apple

In order to have a bumper crop, for many years, gardeners in Tay Ninh province have learned and applied manual pollination techniques for soursop trees. Because in natural conditions, the self-pollination ability of soursop flowers is very low, when the stamens and pistils on the same flower do not ripen at the same time. In addition, the structure of the flower is often downward, the petals do not expand much, so it is difficult to pollinate by insects or wind. If not pollinated or pollinated incompletely, the fruit set rate is low, the fruit is small, uneven, and of poor quality.

Ms. Dang Thi Hoa pollinates the custard apple tree

The technique of pollinating soursop flowers is quite simple, the tools are easy to find but require meticulousness in each step. Before pollination, gardeners must pick long-blooming flowers with stamens that have just turned opaque white to collect pollen. These flowers are usually picked from trees that have been pollinated but still have extra flowers, or have to buy more flowers from other gardens. Next, they remove the petals, put the rest in a paper bag, wrap it in many layers and leave it overnight in the refrigerator.

Early the next morning, farmers sifted the stamens twice, collecting pollen and putting it into plastic straws. The tubes containing pollen were then put into nylon bags and kept in ice baths before being taken to the garden for pollination, to avoid affecting the quality of the pollen.

Flowers selected for pollination are newly bloomed, with petals evenly separated. Farmers simply use a stick to gently push the pollen tube so that the pollen sticks to the flower's pistil bundle. Then, the pollinated flowers are marked by pinching off the tip of a petal.

To achieve high efficiency, people only pollinate flowers when the sun is not too hot, usually in the morning. For large gardens, gardeners have to hire workers to shine lights from 1 am to keep up with the progress of the plants. On rainy days, they have to wait until the weather has completely cleared before pollinating, because the rain prevents the pollen from sticking to the stigma.

Visiting a custard apple garden in Minh Trung Agricultural Service Cooperative (Tan Phu commune), we met Mrs. Dang Thi Hoa and her husband meticulously pollinating each flower. Mrs. Hoa said that the couple has been doing this job for many years and is paid more than 200,000 VND/person/day. Every day, she goes to the garden from 5am and pollinates more than 100 trees in the morning.

According to the experience of this 60-year-old woman, every 3kg of fresh flowers will produce 20 pollen tubes. Each tube pollinates about 10 plants. Flowers pollinated about 5-7 days later will form young fruit. “In general, this job is easy, not too hard, young and old, male and female can do it, but the challenge is that there are many steps so you need to be patient and careful” – Ms. Hoa shared.

Thanks to this method, custard apple orchards now have a fruit set rate of over 90%, much higher than when the trees are self-pollinated (about 65%). Not only that, the custard apples that are pollinated centrally will have a more beautiful appearance and design, bringing high economic value, contributing to strengthening the Ba Den custard apple brand.

After the fruit selection stage, each tree only has 40-50 fruits left. Depending on weather conditions, custard apples can be harvested after about 3 months from pollination. A gardener can harvest 2-3 crops a year. Each tree will produce about 20kg. The most beautiful fruits have a selling price of 70-80 thousand VND/kg./.

Anh Thu

Source: https://baolongan.vn/nghe-thu-phan-cho-mang-cau-a201933.html