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Among the tropical woody bamboos, the Melocanninae is one of the most clearly recognized subtribes morphologically and has also been consistently well delimited in molecular phylogenetic work. The relationships among those genera in this subtribe, however, have been contentious because of poorly understood generic delimitations, in part due to poor specimen material or insufficiently assessed morphological traits, sometimes exacerbated by poorly accessible provenances. We address the phylogenetic and taxonomic status of two groups which together include the largest number of species in this subtribe: the Neohouzeaua-Schizostachyum complex, distributed from India to South China, Southeast Asia and southwest Pacific, and the endemic Indian genus Ochlandra. Three Neohouzeaua species (including the generic type), 12 Schizostachyum species (including the generic type and several species of uncertain placement), together with five species of Ochlandra and representatives of Cephalostachyum, Melocanna and Pseudostachyum were assessed in a molecular phylogenetic analysis together with members of other well-distinguished subtribes. Members of Neohouzeaua and Schizostachyum align into two main groups that were not completely well-supported statistically but which members possess mostly reflexed culm leaf blades, or mostly erect culm leaf blades. Other characters which provide obvious differences between taxa, such as the number of flowers in a pseudospikelet, fusion of filaments into a staminal tube, and presence of lodicules, were inconsistent between these groups. Neohouzeaua and Schizostachyum cannot be clearly distinguished in either morphological or molecular terms, and thus are united under the latter name, which takes precedence. In reviewing names in Neohouzeaua and their basionyms, several lectotypifications are designated. Three new combinations in Schizostachyum are proposed. On the other hand, Ochlandra forms a distinct clade and its monophyly is demonstrated, supported by clear morphological characters.

Melocanna baccifera is a unique bamboo which produces the largest fruits in the grass family. Its gregarious flowering once in 45–50 years in north east India and adjacent regions is a botanical enigma, resulting in a glut of fruits. Proper utilization of M. baccifera fruits is not extant and huge quantities of fruits are left underexploited due to lack of scientific information on their chemical composition and nutritional potential. Here we report the nutritional properties of M. baccifera fruits and the ecological significance of its fruiting. This pear-shaped, fleshy bamboo fruit is rich in amino acids (lysine, glutamic acid), sugars (sucrose, glucose, fructose) and phenolics (ferulic acid). Protein content (free, bound) in M. baccifera fruits is very low. Fruits are rich in saturated fatty acids (palmitic acid), minerals (potassium) and only B series vitamins (B3) are detected in them. Rat feeding experiments showed that M. baccifera fruit alone is not a complete food, but with other protein supplements, it is a valuable food additive. This study could lead to better utilization of M. baccifera fruits during future flowering/fruiting events. These results could also help in the successful management of rodent outbreaks and other ecological problems associated with M. baccifera fruiting.

Hemionitis arifolia, a folklore anti-diabetes fern, was evaluated for its hypoglycaemic and anti-diabetic properties using rats. Glucose lowering effect and anti-diabetes activity were studied using glucose tolerance test in normal rats and alloxan diabetic rats, respectively. When different extracts were tested, the ethanol and, to some extent, the water extracts were found to lower the levels of blood glucose in glucose fed rats. The ethanol extract showed optimum activity at 200 mg/kg. The extract exhibited only marginal hypoglycaemic activity in overnight fasted normal rats and it was devoid of conspicuous toxic symptoms in sub-acute toxicity evaluation in mice. When the alcohol extract was fractionated by sequential solvent extraction, the activity was found in ethyl acetate fraction (50 mg/kg). This fraction containing steroids and coumarins showed anti-diabetes activity in alloxan diabetic rats as judged from serum glucose levels, liver glycogen content and body weight. This fraction is an attractive material for further research vis-à-vis drug development.

Grasses are traditionally considered as wind pollinated, however, field observations confirmed frequent insect visits to grass flowers, suggesting insect pollination. Fruit and seed predators inflict heavy losses to cereals and millets during their growth, maturation and storage. The actual factors guiding insects and predators to grass flowers, fruits and seeds are not clear. Here, we report attractive blue fluorescence emissions on grass floral parts such as glumes, lemma, palea, lodicules, staminal filaments, pollens and fruits in ultraviolet (UV) 366 nm, whereas the stigmatic portions were not blue, but red fluorescent. We characterized the blue fluorescent constituent in grass reproductive structures as ferulic acid (FA). Fluorescence spectra of blue-emitting grass floral, seed extracts and isolated FA on excitation at 366 nm showed their emissions at 420–460 nm. We propose these FA-based blue fluorescence emissions in grass reproductive structures as visual cues that attract pollinators, predators and even pests towards them.