Key techniques for whole-process prevention and control of main diseases and pests of early-maturing peach in South China

Key techniques for whole-process prevention and control of main diseases and pests of early-maturing peach in South China

Peach is a perennial drupe deciduous fruit tree of the genus Prunus of Prunoideae of Rosaceae. With the rise of leisure and sightseeing agriculture, the cultivation area of peach is increasing because of its colorful flowers, rich fruit types, numerous varieties and strong adaptability. According to statistics, the cultivated area of peach in Taizhou City reached 3400 hm2 in 2014. Early-maturing peach fruit is large, crisp, early ripening, high price, has a strong market competitiveness, and is very popular with producers and consumers. However, in recent years, due to the influence of many factors, such as mixed varieties, different tree ages, extensive cultivation and management, and climatic conditions, diseases and pests in Taizhou peach orchards are common, especially peach gum disease, branch blight, brown rot, bacterial perforation, aphids, small heart borer and other major diseases and pests occur seriously in local areas, resulting in fruit drop and fruit rot, which peach farmers can do nothing about, which greatly dampens the enthusiasm of peach planting. It has become a major obstacle to the healthy and sustainable development of peach industry [1-2].

The investigation shows that mancozeb, thiophanate methyl, tebuconazole and chlorpyrifos are commonly used by peach farmers to control diseases and insect pests. Due to continuous use for many years, not only the dosage and frequency are increased, but also the effect is not good, and there are more rotten fruits during the picking period. The fruit surface is not smooth and the commodity is poor [3-4]. For this reason, several combinations of high-quality pesticides were selected in 2016 to explore the key technologies for the prevention and control of main diseases and insect pests in the key growth period of peach. in order to clarify the comprehensive control effect, optimal application period and safety of these pesticides on the main diseases and pests of peach under local production conditions, and to provide scientific basis for production and application, in order to achieve the purpose of reducing damage control, human and animal safety, environment-friendly, efficiency and income increase. The test results are summarized as follows.

1 materials and methods

1.1 Overview of the test

The experiment was carried out in Taoyuan Base of Yangpeng Tou Village, Xiange Town, Xianju County, where the planting area of peach was more than 80 hm2. The peach cultivation and management level of this farmer is representative in the local area. The experimental plot is flat, the soil is loam, the fertility is medium, and early-maturing peaches are planted all around. The peach grew well during the experiment, and the daily management measures of each treatment were basically the same except for different combinations of drugs. Peach gum disease, branch blight and bacterial perforation occurred sporadically and evenly before the implementation of this experiment, but no other diseases and insect pests were found.

1.2 Test medicament

Prevention and control demonstration zone medicament: 32.5% benzoate azoxystrobin suspension (trade name Amimico), 30% benzopropiconazole EC (trade name love seedling), 22% thiazolyl high chlorine fluoride microcapsule suspension (trade name Alika), 11% water soluble fertilizer containing amino acid (trade name Mingyi Shibang), produced by Swiss Syngenta (China) Investment Co., Ltd., provided by Taizhou Agricultural material Co., Ltd. 33.5% quinoline copper suspension (trade name Haizhengbi Green), provided by Zhejiang Haizheng Chemical Co., Ltd., Taizhou Agricultural material Co., Ltd.

Farmers' self-defense zone medicament: 60% azolyl ·Dysenlian water dispersible granule (trade name Baitai), produced by BASF, Germany; 70% thiophanate methyl wettable powder (trade name methyl thiophanate), produced by Jiangsu Longdeng Chemical Co., Ltd.; 10% Jinggangmycin water, produced by Tonglu HSBC Biotechnology Co., Ltd.; 20% Imazole Water Emulsion, produced by Yifan Biotechnology Group Co., Ltd. 80% tebuconazole water dispersible granules are produced by Shandong Biao Biotechnology Co., Ltd., and 40% chlorpyrifos EC are produced by Jiangsu Huifeng Agricultural Chemical Co., Ltd. All the above medications are on the market.

1.3 Overview of experimental treatment and implementation

The experiment was conducted at two points: 3-4 years old (near the foot of the hill) and 6-7 years old (by the side of the road by the village). Each site was divided into three treatments: prevention and control demonstration area, peasant household self-defense area and blank control area, and there were 90 peach trees in each treatment. The peach trees were sprayed evenly with a high-pressure sprayer each time, and the water consumption was based on the uniform wetting of the whole peach tree (667m2 for 60,100 kg). The weather was fine during each application, and there was no rain 24 hours after the treatment. There was no special climatic phenomenon during the whole experiment period.

The specific use of drugs is as follows. Prevention and control demonstration zone: March 2 (before sprouting), application of stone sulfur mixture of 3-5 Pomedo; March 15 (flower bud stage), Shiai Miao 3 000 times + Alika 1 200 times + Yishibang 600 times; April 1 (Xiehua 2gam3), Shi Ammiao 1 500 times + Alika 1 500 times + Haizhengbiilu 1 500 times + Yishibang 600 times On April 17 (young fruit stage), 1 500 times of Ammiao harvest + 1 500 times of Alika + 1 500 times of green + 600 times of Yishibang, and on May 12 (expansion period), 1 500 times of Ammiao harvest + 1 500 times of Alika + 1 500 times of Haizhengbiilu + 600 times of Yishibang. Farmers' self-defense area: March 2 (before sprouting), application of stone sulfur mixture of 3% 5 Bomedoum; March 15 (flower bud), Shibaitai 1 000 times + 70% methyl topiramate wettable powder 800 times + 10% Jinggangmycin water 1 000 times + 40% chlorpyrifos EC 1 000 times; April 1 (Xiehua 2hands 3), application of 20% clotrimazole water emulsion 1000 times + 70% methyl thiophanate wettable powder 800 times + 40% chlorpyrifos EC 1000 times On April 17 (young fruit stage), 80% tebuconazole water dispersible granules 3000 times + 70% methyl topiramate wettable powder 800 times + 40% chlorpyrifos EC 1000 times; May 12 (expansion period). Shi Baitai 1000 times + 80% tebuconazole water dispersible granules 3000 times + 70% methyl topiramate wettable powder 800 times + 40% chlorpyrifos EC 1000 times. No drugs were used during the trial in the blank control area.

1.4 Security investigation

During the whole experiment, the adverse effects of each chemical treatment on peach leaves, branches and results were observed. If drug damage occurs, the type and degree of drug damage are recorded.

1.5 investigation of major diseases and insect pests

Due to the sporadic occurrence of peach gum disease, branch blight and bacterial perforation during the first application, but peach brown rot, aphids and heart borer did not occur yet, so an investigation was conducted before the first batch of peach fruit was harvested. Each treatment was divided into three equal parts and repeated for three times.

Peach gum disease, branch blight. The incidence of all peach trees (30 trees) in each community was investigated, the disease degree was recorded, the disease index and control effect were calculated.

Peach brown rot, small heart borer. Among the three peach trees in each plot, 100 fruits were randomly examined around the crown and the middle and upper part of the inner chamber of each tree, and a total of 300 fruits were examined in each plot. The number of diseased fruits caused by brown rot and the number of insect fruits damaged by small heart borer were recorded, and the control effect was calculated.

Peach bacterial perforation. The three peach trees in the middle of the investigation in each community were randomly examined around the crown and the middle and upper part of the inner chamber of each tree, and each branch was examined 20 leaves from top to bottom, and the disease degree was recorded, and the disease index and control effect were calculated.

Peach aphid. The three peach trees in the middle of each plot were randomly examined around the crown and the middle and upper part of the inner chamber of each tree, the number of residual aphids was counted, and the control effect was calculated.

The grading standard of peach gum disease is as follows: grade 0, the whole plant is normal, there are no glue flow spots, grade 1, the whole tree glue flow spots are 1 / 9, the disease area is less than 5%, grade 2, the whole tree glue flow spots are 10%, 19, 5%, 10%, 10%, 10%, 20%, 29, 20%, 20%, 10%, 20%, 20%, 20%, 20%, 20%, 10%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 10%, 20%, 20%, 10%, 20%, 20%, 20%, 10%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%, 20%,

The grading standard of peach branch blight was as follows: grade 0, the whole plant was normal, no branches withered; grade 1, 1-2 branches of the whole tree died; grade 2, 3-5 branches of the whole tree; 3, 6-10 branches of the whole tree; 4, more than 10 branches of the whole tree died.

The grading criteria of peach bacterial perforation disease were as follows: grade 0, no disease spot, grade 1, 1 disease spot per leaf, grade 2, 3 disease spot per leaf, 3 disease spot, 6 disease spot per leaf, 4 grade, more than 10 disease spot per leaf [5].

1.6 yield determination

First, each treatment is divided into three equal parts, as three repeats. During the first batch of peach fruit harvest, 30 peaches were randomly selected from each plot, and the content of soluble solids (TSS) in pedicel and top and the weight of single fruit were determined. At the same time, three peach trees with similar plant growth were randomly selected in each plot in the unpicked area, and the yield was counted after all batches of picking.

1.7 data processing

All the data were sorted out on Excel 2010, and the analysis of variance was carried out by DPS software [Jishan Huayao].

2 results and analysis

2.1 Security

During the whole experiment, the combination of chemicals in the prevention and control demonstration area had no adverse effects on peach leaves, branches and results, indicating that each combination was safe.

2.2 Control effect

As can be seen from Table 1, the control effects of the prevention and control demonstration areas on peach gum disease, branch blight, bacterial perforation and brown rot were 40.2%, 65.7%, 94.2% and 97.6% respectively, which were 2.6%, 8.0%, 0.6% and 4.3% higher than those in farmers' self-control areas, but the difference was not significant (P > 0.05).

As can be seen from Table 2, the control effects of the prevention and control demonstration areas on peach aphids and small heart borer were 96.8% and 99.1% respectively, which were 2.6 and 1.6 percentage points higher than those in farmers' self-defense areas, respectively, and the difference was not significant (P > 0.05).

Table 1 Control effects of various treatments on peach gum disease, branch blight, bacterial perforation and brown rot

Table 2 Control effects of various treatments on peach aphid and small heart borer

2.3 effect on yield

It can be seen from Table 3 that during the first batch of peach ripening, the weight of single fruit and the content of soluble solids (TSS) in the prevention and control demonstration area were 156.3 g and 10.43% on average, which increased by 46.2% and 3.87% respectively compared with the blank control area, which was very significant (P