Cultivation and management techniques of high quality and high yield of Carya cathayensis

Cultivation and management techniques of high quality and high yield of Carya cathayensis

1 suitable environment of Carya cathayensis

Carya cathayensis is suitable to be planted in the leeward slope area of 200-700m above sea level, and the black limestone soil is the best, followed by the mountain yellow soil. It is appropriate to choose the areas with good light conditions, sufficient rainfall, suitable temperature, deep soil, fertile soil and good drainage and irrigation conditions.

The root system of Carya cathayensis is longer, so in the development area of Carya cathayensis, the deep and loose soil should be selected, which is beneficial to the development of root system and promote the growth of Carya cathayensis. According to the investigation of hickory woodland, the soil of high-yield hickory forest is slightly acidic, and the soil in a few areas is close to neutral, so it should be planted in slightly acidic to neutral soil, which is not only beneficial to the growth of hickory. It can also promote the yield of hickory.

Carya cathayensis is more tolerant to barren soil, but weak to drought. If Carya cathayensis has sufficient water in the growing season, not only the fruit yield is high, but also the fruit quality is high. If there is a long-term drought in summer, it will cause Carya cathayensis physiological fruit drop, resulting in a piece of Carya cathayensis withered tip and scorched leaves, a large number of fruit drop and reduce yield. Carya cathayensis is very sensitive to climate during the period of flowering. If the temperature drops suddenly or continuous rainy weather occurs during the flowering period, a large number of flowers will fall, resulting in a reduction in the yield of hickory in that year.

Carya cathayensis is a wind-pollinated plant, and a small amount of wind is beneficial to its pollination, but the strong wind can easily dry the young leaves and affect the growth and yield of the tree. at the same time, the violent wind will blow away the pecan fruit, which has a great impact on the yield. Therefore, Carya cathayensis should be planted in mountain valleys or valleys, which is not only conducive to the spread of pollen, but also prevent the damage caused by strong winds.

Carya cathayensis is not very strict in light, and generally neutral and shady light is beneficial to its growth. the optimum altitude in the mountain area is 200-700m. The investigation of Carya cathayensis at different elevations shows that Carya cathayensis grows vigorously and develops normally at an altitude of 500-900m. and strong resistance, not easy to breed diseases and insect pests, high yield and good quality of pecan. On the other hand, the occurrence of diseases and insect pests of Carya cathayensis is serious in the area below 200m, and its growth is affected to a certain extent; above 1200m, the growth of Carya cathayensis is poor and the yield is very low. At the same time, the lower the latitude, the higher the vertical distribution of Carya cathayensis.

Carya cathayensis is suitable to grow in the leeward area, at the same altitude, due to different topography differences, resulting in different microclimate, affecting its growth and fruit. In the hilly area with lower altitude, the light is stronger and the temperature is higher. The main limiting factors for the development of Carya cathayensis are high temperature and drought, which should be planted on shady slope or semi-shady slope. In high altitude areas, due to the influence of high humidity and low temperature, it is better to plant pecans on sunny slopes.

2 main cultivation measures

2.1 suitable site and suitable tree

The natural distribution and growth results of Carya cathayensis in Ningguo City should be investigated before planting. Only in this way can we choose a suitable planting site for suitable trees. First of all, we should choose the area with leeward in the valley, rainfall, strong light and suitable temperature and humidity. And Carya cathayensis has a strong demand for soil, which requires a slightly acidic soil with deep soil layer, loose topsoil, compact core soil, fertile soil, strong water permeability and good water and fertilizer conservation. In the areas with less rainfall, the soil with deeper soil layer should be selected for afforestation.

2.2 selection of improved varieties

The mother seed of Carya cathayensis is very important for the cultivation of improved varieties, and the mother seed is used for sowing and raising seedlings before the cultivation of improved varieties, so the selection of mother species is more strict. select strong-aged trees with exuberant growth, no occurrence of diseases and insect pests, good crown type, high yield per plant, large and full stone, strong resistance and so on. The harvest time of mother tree seeds should be delayed by more than one week than the normal fruit. After the fruit was harvested, Lianguopu was spread out in a well-ventilated room and sown in the forest after the middle of October.

2.3 planting techniques

The soil preparation is carried out before planting, and the banded or block mode is preferred. Banded land preparation is generally suitable for mountainous areas with large slope; if the slope of planting land is relatively slow, it is appropriate to use block land preparation to improve the utilization rate of woodland, and the general planting specification is 1 × 1m. In order to promote the survival of newly planted seedlings, the surrounding weeds and shrubs should be retained to provide shade. At the same time, the planting hole was dug a little deeper in order to extend the root system and improve the survival rate of seedlings. In addition, the planting density has a great influence on Carya cathayensis. Carya cathayensis should be sparsely planted properly. At the initial stage of planting, the density should be controlled at 450,600plant / hm2, and finally maintained at 300,450plant / hm2, so as to achieve the goal of high quality and high yield.

2.4 Water and fertilizer management

2.4.1 weeding and fertilization

Weeding can reduce the competition for water and nutrition during the growth of weeds in Carya cathayensis forest, and can significantly improve the yield and quality. As herbicides have a certain impact on the soil and the environment, artificial weeding is advocated and can be combined with intertillage. When the amount of grass is too large and manual weeding is inconvenient, pollution-free chemicals can be selected to weed properly.

Nitrogen fertilizer and phosphorus fertilizer should be the main fertilizer for Carya cathayensis. Fertilization was carried out before flowering and after fruit drop respectively to promote flower bud differentiation and fruit development and increase fruit yield. Carya cathayensis should be fertilized with more organic fertilizer, biological fertilizer and less chemical fertilizer. Fertilization can reduce the size of Carya cathayensis, maintain high and stable yield and improve the quality of Carya cathayensis. According to the growth situation of Carya cathayensis, ring-shaped ditches were opened around the roots of pecans, properly sprinkled with urea, compound fertilizer or deep-buried base fertilizer, and then covered with soil.

2.4.2 Water management

Carya cathayensis has a high demand for water. It is afraid of both long-term drought and soil stagnant water. the amount of soil water content has a great influence on the growth and development of Carya cathayensis. Too much water is easy to cause the growth and fruiting of Carya cathayensis. The root soaked in water for a long time will cause tree death. Forest investigation shows that Carya cathayensis grows in well-drained soil with large crown, high yield and good quality. A long period of drought can also cause poor growth of pecans, fruit shedding, and even death of trees. Therefore, according to the soil moisture condition, pecan watering and drainage should be done in time.

2.4.3 intercropping

According to the investigation, intercropping has a significant effect on Carya cathayensis. Carya cathayensis grows slowly and generally takes 20 years to enter the full fruit period. at the same time, young trees prefer shade, interplanting can effectively block strong light and improve soil drought in summer. Pecans can be planted just a few years ago, and the trees are small, and cash crops such as corn, legumes and tea can be planted in the spare parts of the forest to increase the income of interplanting crops.

2.5 shaping and pruning

Pruning has a great effect on the growth and yield of Carya cathayensis, and the quality of pruning has a great effect on the growth and yield of Carya cathayensis in the second year. First of all, the peripheral crowded cross branches and overlapping branches should be trimmed, focusing on cutting off the weak branches and disease and insect branches, and thinning the long branches of the inner rifles. Since then, if too many branches are thinned irregularly every year, the general pruning amount should be controlled at about 25% of the total branches.

2.6 Flowers and fruits

In the flowering and young fruit stage, it often leads to unsuccessful pollination or early fruit shedding, but spraying and drying with chemicals and exogenous hormones can obviously improve the fruit setting rate of Carya cathayensis. The chemicals used in the fruit growth period, the concentration is slightly lower, in the later stage of growth can be properly increased concentration, can effectively protect the fruit. At the same time, artificial pollination can be carried out during the peak blooming period of Carya cathayensis female flowers, especially in long overcast and rainy days, which can also significantly improve the fruit setting rate of Carya cathayensis.

2.7 harvesting

It should be harvested in late September, that is, about a week after White Dew, when the pecan has basically reached physiological maturity, the exocarp turns yellowish brown and the fruit begins to fall off. Personal safety should be paid attention to when harvesting pecans, and attention should be paid not to damage branches and buds during harvest, so as not to affect the yield of pecans in the second year. At the same time, we can use falling agent to harvest pecans. Spraying ethephon is an ideal method to accelerate the fall of pecans at present. Ethephon with a concentration of 300000 mg/ is often used to spray pecans.

2.8 Disease and pest control

The main pests of Carya cathayensis are leaf-eating pests and stem borer. Among them, the main leaf-eating pests are hickory aphid, hickory boat moth, green moth and so on, and the trunk pests are mainly Monochamus alternatus, mulberry longicorn beetle, coffee bark moth and so on. If the leaf-eating pests occur seriously, the leaves of Carya cathayensis can be eaten up, resulting in the weakening of the tree, the decrease of the yield of Carya cathayensis, and the occurrence of diseases; the stem borer does more harm to the Carya cathayensis, which can cause the branches to die and wind-break easily, and even cause the death of the whole plant if it occurs seriously. The serious and common pecan diseases occurred locally are pecan canker, branch blight, leaf blight and so on. Carya cathayensis disease caused the greatest damage to Carya cathayensis, with a wide occurrence area and serious damage, resulting in the death of trees within a few years.

The prevention strategy should be implemented in the prevention and control of diseases and insect pests of Carya cathayensis. Adopt the way of suitable land and suitable tree, choose the site planting environment suitable for its growth, and should not blindly expand the planting area of pecan, reasonably control water and fertilizer, naturally form the size of the year, enhance the growth of trees and improve their resistance to stress. Enhance the ability of pecan to resist diseases and insect pests. For serious diseases and insect pests, pollution-free chemicals should be used in time to prevent and control serious diseases and insect pests so as to avoid further expansion of losses.