This year, Korla primiparous Korla pear discovered the “Stone pox disease” harm caused serious losses to growers. According to the survey, the film Liyuan varieties for Taiwan honey Sydney, most planted in the spring of 2008, some planted in the spring of 2009. In July this year, the occasion coincided pear harvesting, farmers found a large number of pome surface uneven, crooked fruit shape, very neat and well-spaced, that is, to the agricultural station consultation. Subject to verification and to ask County Bureau of Agriculture Fruit professional experts, the disease of pear stone pox disease. Initial investigations revealed that: film Liyuan strains of incidence of about 35-40%, 80-90% of the incidence of serious plant fruit, whole plant pear knot the pome almost no value of the goods or food value, serious loss. In recent years, the county and other areas off the kinds of pears boom, source of a wide variety of seedlings, it is inevitable to fish, and vulnerable to the introduction of the sick pear seedlings, therefore, to remind growers: kinds of Korla Pear should beware of “pear stone pox disease risk . The following is the online search was related to a pear stone pox disease for growers reference.
Symptoms: Stone pox disease harm the fruit and bark. First of all realizable symptoms Petals 10 to 20 days the young fruit, dark green area in the fruit epidermis, depression illness District stunting, fruit malformation. Stone cells accumulate within the recessed area surrounding the pulp. Cells into brown, stone fruit ripening. Loss of food value. The some diseases Sure deformation fruit surface only a slight bump, but the flesh is still brown stone cells. If the disease rate with a sick tree year difference in between 18% to 94%.
New slightly diseased trees, branches and stems bark cracking, under which tissue necrosis. Cork protrusions old trees on the dead skin. Bark necrosis severity differ due to susceptible varieties. Foliar symptoms are not common, pumping hair sometimes early spring before the leaves appear small green chlorotic spots.
Pathogens: viruses (Apple stem pitting virus, ASPV)
The occurrence regularity: pears varieties such as Bao Sike, Kou Mies and Sai Keer symptoms heaviest, while minor symptoms in Hardy, Kangfolunsi Bartlett varieties. The many Oriental pear varieties infected without showing symptoms, but the infected tree growing recession, generally cut from 30% to 40%. Plow stone pox virus is mainly transmitted by grafting the scion or rootstock carriers of the virus is the main infection source of the disease. The pear stone pox virus infection, the whole plant with a virus, not but proliferation lifelong harm.
Prevention and control measures:
Nurture and planting virus seedlings: selection of disease-free rootstock and scion nurturing seedlings, rootstocks to avoid root suckers. Strict selection of virus-free scion. The diseased trees not use virus-free scion grafting the head.
2. Improve tree resistance: strengthen management to increase organic fertilizer, proper pruning, dry weather timely irrigation, attention to drainage during the rainy season.
Excluding the proceeds from the disease tree: orchard found diseased trees should be rooted plane out over 1 to 2 years to confirm the absence of living roots tree replanting and health.