【Objective】 The study aims to accurately verify sympodial bamboo hybrids, clarify genetic relationships between hybrids and their parents, and develop applicable fingerprints. 【Method】 We screened, tested and analyzed 30 pairs of randomly selected published bamboo simple sequence repeat (SSR) primers using hybrids derived from Bambusa multiplex × Dendrocalamus latiflorus and B. multiplex × B. chungii crosses. 【Result】 According to the results, six SSR primer pairs (P8, P9, P18, P19, P20 and P27) were suitable for the hybrid identification and genetic analysis of the B. multiplex × D. latiflorus cross, which revealed that all 34 progenies were true hybrids (100%). Six SSR primer pairs (P2, P9, P10, P11, P20 and P28) were suitable for the hybrid identification and genetic analysis of the B. multiplex × B. chungii cross, which revealed that 54 of the 59 progenies were true hybrids (91.5%). Hybrids of the B. multiplex × D. latiflorus cross inherited more maternal alleles, while hybrids of the B. multiplex × B. chungii cross inherited more paternal alleles. The alleles detected using SSR primers were used to construct hybrid fingerprints of the two crosses for variety protection. 【Conclusion】 The SSR primers could be used to effectively verify sympodial bamboo hybrids as the progeny inherited alleles from different parents at varying probabilities in different crosses. In addition, the development of hybrid fingerprints could facilitate variety protection.
【Objective】 Strip cutting of moso bamboo forests can realize their mechanized management. We aimed to provide a scientific basis for the reasonable management of bamboo strip cutting, biomass allocation and allometric growth of Phyllostachys edulis with different cutting widths. 【Method】 Whole forest clear-cutting of P. edulis forests of different widths was conducted in December 2019. The number of new bamboos, diameter at breast height (DBH), clear bole height and height of the bamboo at different cutting widths (0, 3, 9 and 15 m) were counted in August 2020. The biomass of branches, leaves and stems of new bamboo were investigated, and the biomass allocation characteristics and allometric growth relationship of aboveground components were analyzed. 【Result】 Strip cutting increased the number of new bamboos: the trend was first increase and then decrease, and the number reached the maximum value in the 9 m cutting width. With the increase in cutting width, the bamboo height (CBH), DBH, clear bole height, and ratio of CBH to DBH of new bamboo decreased, and the fresh branch, leaf, stem weight and total biomass decreased significantly. Strip cutting could improve the leaf strength and ratio of bamboo height to DBH of P. edulis, especially the proportion of leaf distribution and leaf relative biomass. Strip cutting did not change the isokinetic growth relationship between the stem-total biomass of P. edulis but significantly affected the relative growth rate of branch-total biomass and leaf-total biomass, which changed from allometric growth to isokinetic growth.【Conclusion】 The results showed that strip cutting balanced resource allocation among the components through physiological integration, the allometric growth relationship was changed, and the morphological plasticity of new bamboo was induced.
【Objective】 To provide a theoretical basis for selecting the irrigation time of Phyllostachys edulis stumps, the differences in chemical metrology and physiological characteristics of stump roots of P. edulis under different irrigation times were studied. 【Method】 The cutting pile of P. edulis stumps was taken as the research object. Four treatments were used: irrigation for 0 days (control, CK), irrigation for 180 days (T1), irrigation for 360 days (T2), and irrigation for 720 days (T3). The differences of root stoichiometry, relative conductivity, malondialdehyde (MDA) content, root activity, antioxidant enzyme activity, and soluble protein content in four stumps of P. edulis after different irrigation times were analyzed and compared.【Result】 The results showed that the content of carbon (C) in the roots of P. edulis stumps increased with increasing irrigation time, but the content of nitrogen (N) and phosphorus (P) increased first and then decreased; m(C)/m(N) and m(C)/m(P) increased continuously, and m(N)/m(P) remained relatively stable. The activities of various oxidases, relative conductivity, and MDA content of P. edulis stump roots increased with increasing irrigation years, while the activities and soluble protein contents of P. edulis stump roots decreased with increasing irrigation years. 【Conclusion】 According to the comprehensive physiological indexes, the results showed that the irrigation effect of P. edulis stumps was satisfactory within 360 days.
【Objective】 A reasonable bamboo forest population structure leads to a high and stable yield in bamboo forests. Therefore, our aim was to optimize the population structure of bamboo stands, and consequently, improve shoot yield.【Method】 Using the conventional stocking bamboo conservation method as the control treatment, we evaluated the shooting ability, yield and economic benefit of long-period stocking bamboo conservation forests.【Result】 Under the long-period stocking bamboo conservation mode, cutting one bamboo shoot could increase shoot buds by 1.8 to 3.0 shoot buds. It was also observed that the eight stubble generations were expended during one conservation period and 8.0-10.2 shoots were formed in each stubble generation, which was more than the shoot number from the stocking plant. Additionally, the distance between young bamboo and stocking bamboo was 64.4 cm on average, which was much further than that of 27.0 cm in the control treatment. Furthermore, the shoots emerged 15 days in advance and a delay of 15 days was seen before it stopped producing shoots. Its yearly yield was 37.9 kg per cluster, which is 22.1% higher than that of the control treatment. Moreover, its yearly revenue was 504.3 Yuan per cluster, which is 26.86% higher than that of the control treatment; while its yearly profit was 281.4 Yuan per cluster, which is 68% higher than that of the control treatment.【Conclusion】 The long-period stocking bamboo conservation mode prolonged the shoot period, improved the yield and economic benefits, reduced the number of stocking bamboo plants, and further reduced the labor intensity of bamboo stump removal and old bamboo cutting. The inter-bamboo distance was also more conducive to mechanized operations. The long-period stocking bamboo conservation mode is a simple and practical technical measure that is worth popularizing.
