Prevention and control of main diseases and insect pests in planting jujube

1. Major diseases

1. Jujube rust. The disease mainly damages leaves and sometimes fruits. The damaged leaves scattered light green dots on the back, then gradually turned grayish brown, and finally the disease spots became yellowish brown, resulting in protruding summer spore piles. In the place where the leaves are facing the pile of summer spores, there are irregular small brown-green spots, which gradually lose their luster and become yellowish-brown corner spots. Most of the germs overwintered on the diseased leaves. After the rainfall in late June, the overwintering spores began to sprout and invade the leaves, and the disease began in the middle of July. The pathogen was continuously re-infected from August to September, and a large number of seriously damaged leaves began to fall. Rainy and high humidity are the main conditions for the epidemic of jujube rust.

Control measures: ⑴ to strengthen cultivation management, increase the application of organic fertilizer, so that the tree growth is strong, improve the tree disease resistance. ⑵ in the winter dormant period, through reasonable shaping and pruning, so that the garden to maintain good ventilation and light transmission conditions, thoroughly sweep the diseased leaves, focus on burning, and reduce the overwintering bacteria. ⑶ spray control: in late June, before the bacteria began to invade, spray protection, once every 15-20 days, 3-5 times. The commonly used agents are 50% carbendazim 1000-fold, 200-fold Bordeaux solution, 50% carbendazim 600-fold solution, 25% trimethoprim wettable powder 1000-1500 times, etc., the effect is good.

2. Jujube anthracnose. The disease mainly harms jujube fruits as well as leaves. Fruit damage, the initial appearance of brown water-stained spots, after expansion, into a nearly round sunken spot, the spot expanded dense gray to black particles, resulting in fruit drop, the taste of the diseased fruit is too bitter to eat, and the leaves will turn yellow and fall off. It will aggravate the illness when it is rainy.

Control measures: ⑴ to strengthen fertilizer and water management, improve soil, so that drought can be irrigated, waterlogging can discharge, increase the application of organic fertilizer, promote the healthy growth of trees, and improve the ability of disease resistance. ⑵ clean orchard: burn or bury all the fallen leaves and fruits in the orchard after falling leaves. ⑶ chemical control: spray Baume 5 degree stone sulfur mixture once before jujube sprouting. 200 times lime Bordeaux solution was sprayed once in the first and middle of June. Fungicides were sprayed once in mid-July, late July and early August respectively. The commonly used agents are 65% Dysen zinc 500x liquid, 50% carbendazim 1000-fold solution, 75% chlorothalonil wettable powder 600x liquid, 200x lime Bordeaux liquid and so on.

3. Jujube madness. The disease is mainly harmful to jujube and wild wild jujube, and it is a destructive disease of jujube. After the jujube tree was infected, both the aboveground and underground parts showed abnormal growth state. The aboveground part is characterized by the change of flowers and leaves, the clump of branches and leaves caused by abnormal bud development and growth, and the yellowing and curling of young leaves in the shape of spoons. The underground part is mainly manifested in the growth of roots and tillers. The young trees will die after 1-2 times of disease, the big trees will get sick, and gradually wither and die in 3-6 years. Jujube mad disease is transmitted by grafting or by piercing of leafhopper pests in the field.

Prevention and control measures: ⑴ eradicates diseased plants and diseased root tillers to prevent infection. ⑵ selected disease-free scion and grafted to breed seedlings. ⑶ selects varieties with strong disease resistance, strengthens cultivation management, and promotes the healthy growth of trees. ⑷ control vector pests, spray 20% pyrethrin 3000 times or 10% imidacloprid 3000 times.

II. Major insect pests

1. Peach heart borer. One or two generations occur every year in northern China, and the aged larvae are used as winter cocoons in the soil to survive the winter. they are unearthed in the middle of May the following year, continuously unearthed in the first and middle of June, and are unearthed at the peak in mid-June. The adults Eclosion and oviposition in July, and the larvae begin to hatch and decay fruit in mid-July. The larvae live in the fruit for about 25 days, lose fruit and form cocoons and pupate, and the second generation continues to occur. After mid-July, the larvae of fruit decay continue to occur. After fruiting, most of them fall into the soil and form cocoons to survive the winter, and only one generation occurs.

Control measures: ⑴ tree plate soil or film mulching, before the larvae are unearthed, cultivate and press the soil within 1 meter around the tree trunk to prevent the larvae from being unearthed. Before mulching, spread 5% phoxim granules on the ground, then hoe shallowly. ⑵ should be used at the right time. When the egg-fruit rate reaches 1-2%, start spraying control. Spray 2-3 times in a row, once every 15 days, 20% permethrin 2000-3000 times, 30% peach Xiaoling EC 1500 times, spray carefully.

2. Jujube inchworm. The larva is the tender bud of harmful jujube, the leaves and flower buds occur one generation a year, and the pupa overwinters in the soil 10-15 cm deep around the canopy. In late March of the following year, the pupae are feathered into adults. After mating, the female adults do not have wings and have to climb onto the trunk to lay eggs. After about 25 days of egg period, the larvae hatch from mid-late April to mid-May to do harm to the trees. The 1st-3rd instar larvae eat little, mainly harm tender leaves, and the 4th-5th instar larvae eat much more. The leaves are often eaten up, and after the 5th instar development, the larvae begin to pupate from late May to mid-June over the summer and winter.

Control measures: ⑴ combined with deep ploughing soil in winter to pick and kill overwintering pupae. In early March, ⑵ tied a film about 10 cm wide at the base of the trunk 20-25 cm above the ground to prevent female adults from spawning. Every morning and evening, they artificially killed adults under the tree, or sprayed pyrethroids around the trunk to kill hatched larvae. ⑶ tree spray control, if the tree is not thoroughly controlled, there is still harm to the tree, can be sprayed with 25% diflubenzuron 2000 times solution to control.

3. Jujube armyworm. Also known as echinococcosis, the larvae harm leaves, flowers and fruits, and the jujube twigs are spun together to roll the leaves into dumplings, or eat the flesh from the stalk, resulting in the early fall of the damaged fruit. The insect produces three generations a year, the pupa overwinters as a cocoon under the old warped skin and in crevices, begins Eclosion in late March of the following year, reaches its peak in the first and middle of April, copulates 2-4 days after Eclosion, lays eggs 1-2 days after mating, and the egg period is 10-15 days. the peak period of the first generation larvae is in early May, the peak period of the second generation larvae is from late June to early July, and the third generation is in the first and middle of August.

Control measures: ⑴ began to bind grass handles on tree trunks in early September to induce larvae to pupate on them for overwintering. In winter, grass was collected, burned or buried deeply. ⑵ scrapes off the old warped skin in winter to reduce the source of overwintering insects. ⑶ spray control, pay close attention to the first generation larva control, timely spray control in the larval period, with 1000 times of trichlorfon and 20% fenpropathrin 3000 times solution alternately, the effect is better.