In an effort to develop a sustainable protocol for the micropropagation of a shy suckering elite chrysanthemum cv. Arka Swarna (yellow pompon type), in vitro cultures were established using surface-sterilized nodal microcuttings (1-1.5 cm) from polyhouse-grown plants on MS medium containing 3% sucrose, 0.25% phytagel, and 5 μM benzyl adenine (BA) or kinetin. Microbial contamination in the range of 6-24% was encountered during the first in vitro passage. Apparently clean cultures after one passage on MS basal medium were transferred to medium with BA or kinetin (0, 1, 5, 10, or 20 μM) in culture bottles, and were monitored for eight in vitro passages (1 mo. each) for growth and microbial contamination. Plant growth regulator (PGR)-free medium was the best for sustainable micropropagation over successive in vitro passages yielding a single shoot from cultured microcuttings. Higher cytokinin levels inhibited rooting and induced one or more shorter shoots with close nodes resulting in low propagation rates. All apparently clean stocks revealed covert endophytic bacteria during tissue-indexing using bacteriological media. Three distinct bacterial morphotypes were isolated from such stocks, identified based on 16S rRNA gene sequence analysis as different morphotypes of Curtobacterium citreum. The endophytes tended to show obvious growth on chrysanthemum culture medium with increase in cytokinin levels (5-20 μM), but such growth was not noticed in inoculations on MS medium without plants. Sustainable micropropagation of cv. Arka Swarna for more than 2 yr with the resident endophytic bacteria in covert form was realized on PGR-free MS medium giving a net propagation rate of three to four times over a subculture cycle of 2-3 wk.

The general equations available/developed for forest/wild mango trees based on measurement of diameter at breast height (DBH) (cannot be used) are not applicable for mango orchards which are predominantly established with grafted plants. Hence allometric equations were developed with destructive sampling of grafted mango trees. The selected parameters showed that allometric parameters were significantly related with age of the trees. The proportion of roots (22%) in grafted mangos was found to be higher than those reported for tropical forest trees (18%) with a R ratio of 0.291. The biomass expansion factor (BEF) varied with age. Initially the BEF was very high followed by a decreasing phase and finally a steady phase by and large attained stability beyond 20 years. The equations generally fitted the data well, and in most cases more than 50% of the observed variation in biomass was explained by primary branch girth (PBG) × number of primary branches (NPB). All equations were statistically significant (p < 0.05) for both scaling parameters, a and b. Based on the R 2 values the best fit model for estimation of above ground biomass of grafted mango trees is a power model using PBG × NPB as the best dimension: There was a good agreement between the observed and the predicted biomass using this equation.

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Visceral leishmaniasis (VL) or kala-azar is transmitted by parasite-infected sandflies. The female sandfly Phlebotomus argentipes Annandale & Brunetti (Diptera: Psychodidae) carries the protozoan parasite Leishmania donovani (Kinetplastida: Trypanosomatidae) in its gut and injects the pathogen along with its saliva into the bloodstream of a human host. This article reports the successful setup of a very productive laboratory insectarium-based P. argentipes colony, by optimizing breeding conditions and choice of laboratory host animal for blood feeding of the female sandflies. The work also suggests that the source of blood feeding is a critical parameter for egg laying and maturation, which are essential for the maintenance of laboratory colonies of such hematophagous insects.

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