The selection and quality of rubber tree bud patches is a critical factor influencing the survival rate of bud grafting in rubber tree mini-seedling buddings. Currently, the selection process relies heavily on the individual experiences of budding workers, who choose the bud sticks and cut the patches based on personal judgment. This method necessitates sorting and shipping the mini-seedling buddings in batches prior to their departure from the nursery, which in turn elevates labor costs. In this study, we trimmed the leaves from the petiole buds on the bud sticks of the rubber tree variety Reken 628. Following the detachment of the petioles and the transition of leaf scars from green to brown, we proceeded to cut the bud sticks. Both the scale buds and petiole bud patches were excised, and the various types of leaves were documented accordingly. We measured the quantity of each bud type present in the canopy and collected growth data, including the moisture content of the buds, as well as the length, width, and thickness of the bud scars, in addition to the length and width of the bud eyes. Our findings indicate that the size of the bud scar is not a reliable indicator of bud eye size. Notably, the quality of leaf-clipped buds surpasses that of those with retained leaves, with the buds from the third leaf whorl exhibiting the highest quality when subjected to leaf clipping. It is essential to increase the watering frequency to ensure that the leaf-clipped bud sticks maintain adequate moisture, which facilitates the cutting of bud patches and the removal of bud wood. This practice helps preserve the integrity of the bud eye post-peeling, ultimately enhancing the survival rate of bud grafting.
Rubber seedling rootstock cultivation is the first step of rubber budding propagation. However, there is still a lack of systematic studies investigating leaf phenology effect on rubber seedling nursery. In this study, leaf phenology, stem diameter, plant height and the chlorophyll parameters were observed at six periods. The results showed that bronze stage was the rapid growth and regulation stage of plant height, bronze stageⅠwas the rapid growth and regulation stage of stem diameter, and light green leaf stage was sensitive to environmental temperature. Taken together, leaf phenology affects the growth of rubber seedlings, and understanding phenological effects helps to regulate the phenological process to raise rootstock seedlings.
In China, harvest cost of natural rubber is high due to a declining rubber price, less favorable agroclimate, and skilled tapper labor shortage. Reduction in cost of latex harvest by tapping machine in a straight line will make rubber production more cost effective. To evaluate the feasibility of tapping in a straight line, a comparison of two tapping practices (horizontally/traditionally tapping and vertically/straightly tapping) was conducted in clone Reyan88-13. Compared with horizontally tapping, vertically tapping increases dry rubber content and Mg2+ content, significantly decreases initial latex flow velocity, dry rubber yield per cut length, reduces thiols content and Cu2+ content, and alters physical and mechanical properties of raw rubber and vulcanizate. Taken together, vertically tapping reduces tapping intensity, alters physical and mechanical properties of raw rubber and vulcanizate at the cost of less rubber latex yield.