The physiological function of bamboo shoot sheaths is still unclear. In the present study, we investigated the anatomical and physiological influences of bamboo shoot sheaths on internode elongation by longitudinally striping parts of sheaths. The internodes would bend toward the bare sides during night. The results showed that amounts of water leaked at the cut of shoot sheaths during night, which impeded the increase of water, water pressure and assimilate transport rates, and decreased starch and soluble sugar catabolism in the bare side of the internodes. A higher level of water pressure and sugar metabolism increased the vacuole expansion and promoted the cell expansion in the outer sides as compared to the bare sides. The bending growth of internodes was mainly due to the significant differences in cell expansion, which was led by the difference in water pressure and sugar hydrolysis levels between the inner and outer sides. Bamboo internode elongation mainly relied on the increase of water pressure and soluble sugar concentration. Shoot sheaths played an important role in the rapid growth of bamboo shoots as a controller in water and assimilate transportation. This study gave a new insight into understanding the rapid growth mechanism of bamboo plants.

Non-structural carbohydrate (NSC) dynamics in different bamboo types underlie the different management practices of bamboo plantations. The changes in moisture, soluble sugars, and starch content in response to phenological variations in different types of bamboo were measured to reveal the NSC dynamics in different bamboo forests for high yield. It was reported for the first time that new leaves of monopodial bamboo started sprouting after the completion of branching, while sympodial bamboo extended new leaves and branches simultaneously. NSC accumulation for shooting lasted about eight months for monopodial bamboo but only a short interval of two to three months for sympodial bamboo. The moisture content in different types of bamboo showed a similar trend of increasing from March to July and then decreasing until the coming January. From March to May, particularly in March, irrigation was required for the shooting of monopodial bamboo, whereas the shoot buds in sympodial bamboo showed sprouting, branching, and leafing. Total NSCs in different bamboo types remained relatively high in March, gradually decreased to the lowest in July, and then increased continuously until the coming January. Average soluble sugar and starch contents showed the same trend as the total NSCs in different types of bamboo. During the period from March to July, large amount of photoassimilates were required for shooting and height growth and then for branching and leafing in monopodial bamboo. Abundant photoassimilates were also required for branching, leafing, and shoot bud differentiation, as well as for subsequent shoot germination in sympodial bamboo. Thus, fertilizer application to both monopodial and sympodial bamboo plantations should be scheduled in early May and late July. Given the moisture, soluble sugar, starch, and total NSC content, January was the best season for harvesting monopodial bamboo for high production and future growth, whereas for sympodial bamboo, November was the best season.

Reasonable management could produce the good growth of bamboo plants. There are few studies in bamboo that integrate phenology and ecophysiological traits; in this case, water relations, photosynthetic rates and carbohydrate content in different organs of Neosinocalamus affinis were determined. The moisture content was easily affected by the local precipitation and showed a similar trend in leaves and branches, with the highest values in July and August, but did not vary significantly between vegetative phenological stages in culms. The emergence and growth of shoots caused an apparent decrease in the moisture content of 1-year culms. NSC content showed a similar trend in culms and branches in classes of different ages and decreased progressively from March through November and then increased in the following months. Net photosynthetic rate and transpiration pull showed the highest values in July and then decreased constantly, which implied that a great deal of water was consumed for photoassimilate synthesis. The net photosynthetic rates of leaves were significantly affected by the water status of culms in the dry season, but correlated significantly only with the leaf water content in the wet season for the sufficient water supply. The transpiration pulls, water potential and sap flow rates revealed the water status of culms better than the water content of culms. The shoot germination and growth of N. affinis were more dependent on the photoassimilate accumulation in the early stage from May to July. There was no real dormancy period for N. affinis due to its apparent photoassimilate accumulation and water flow in January. This suggested that proper irrigation was essential during leaf and branch extension during the dry season.

The moisture, ash, and silicon content, as well as the phytolith morphotype and concentration in the tissue-cultured, seed-cultured, and grafted seedling leaves of Dendrocalamus brandisii were determined to investigate the differences in silicon uptake and phytolith morphology in the leaves from different rearing methods. The results showed that ash, silicon content, and phytolith concentration were higher in the mature leaves. Tissue-cultured seedlings had a significantly higher moisture content than grafted seedlings. Ash and silicon demonstrated the same order of grafted seedlings > tissue-cultured seedlings > seed-cultured seedlings. The highest phytolith concentration was found in tissue-cultured seedlings. The phytolith morphotypes in D. brandisii seedling leaves raised by different methods were identical and grouped into eight morphotypes. The phytolith assemblage was characterized by a high frequency of bilobate and saddle, accounting for more than 60%, whereas the morphotypes of elongate, blocky, flabellate, and circular phytoliths accounted for the smallest proportion, normally all below 4.5%. The phytolith size demonstrated an increasing trend in the maturing leaves. The sizes of bilobate, saddle, and acute phytoliths expanded the fastest in tissue-cultured seedling leaves, implying rapid growth of the cell in tissue-cultured seedlings. Accordingly, the tissue-cultured seedlings contained more silicon and phytoliths of larger sizes, which could be a better choice of stock supply for establishing large-scale plantations. If the stock of the seed-cultured and grafted seedlings is to be used, silicon fertilizer application is an optimal option to boost seedling growth.

High-quality genomic DNA extraction is fundamental for the study of gene cloning and expression in plants. Therefore, this study evaluated several methods for extracting genomic DNA from shoots of ... Tweetable abstract The efficiency of three DNA extraction methods was assessed for the shoots of four Dendrocalamus species, with the commercial DNA extraction kit method demonstrating optimal perf... METHODS SUMMARY Genomic DNA was extracted from the shoots of four Dendrocalamus species (sample mass: 0.1 g; n = 3/species/method) using three different methods: a commercial DNA extraction kit met...

The differences in the response of the leaves of different bamboo types to sudden snowfalls in winter were analyzed in order to provide scientific references for the introduction and cultivation of cold-resistant bamboo species and to provide new theoretical information on bamboo afforestation and disaster reduction. A total of nine bamboo species were selected to analyze the physiological and chemical changes in the leaves caused by a sudden snowfall. The results showed that sudden snowfall in winter led to a decrease in the moisture, soluble sugar, and starch contents in the leaves of all of the bamboo species analyzed, but there were increases in the contents of proline, MDA, and H₂O₂ and in the ratios of AsA/DHA and GSH/GSSG. Both the enzymatic activities (SOD, POD, CAT, APX, DHAR, GPX, and GR) and non-enzymatic antioxidant contents (AsA and GSH) were increased after the snowfall, which indicated that the sudden snowfall caused an increase in the antioxidant abilities in the leaves of all bamboo species analyzed. Different bamboo species adopted different strategies for resisting the freezing damage caused by the sudden snowfall. The prevention and mitigation of snow disasters in winter can be scientifically carried out in bamboo forests according to their tolerance abilities.