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In Bangladesh little leaf disease was observed in brinjal (Solanum melongena L.) and in periwinkle (Catharanthus roseus). Phloem‐inhabiting phytoplasmas were consistently detected in both species of diseased plants using transmission electron microscopy (TEM) and polymerase chain reaction (PCR) techniques. The shape, size and within‐tissue distribution of phytoplasmas appears to be similar in both hosts. Furthermore, the molecular characterization and identifications of observed phytoplasmas were carried out based on restriction fragment length polymorphism (RFLP) patterns of PCR‐amplified products (1200 bp) using phytoplasma‐specific universal primers and sequencing analysis of both 16S ribosomal DNA (rDNA) and intergenic spacer region (ISR) of 16S‐23S rDNA phytoplasma genes. The patterns of RFLP analysis with seven restriction enzymes exhibited a similar pattern for both phytoplasma strains. The sequence homology between these two strains showed 100% similarity based on 16S rDNA and 16S‐23S ISR. Therefore, in Bangladesh the causal agents of brinjal little leaf (BLL‐Bd) and periwinkle little leaf (PLL‐Bd) are probably the same or closely related phytoplasma strains. These strains, are very close or identical to the strain of brinjal little leaf phytoplasma in India (BLL‐In), belonging to the clover proliferation group (Lee et al., Int. J. Syst. Bacteriol. 48, 1153–1169, 1998; Seemuller et al., J. Plant Pathol. 80, 3–26, 1998).

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In a two-year study ten commercial date palm varieties were evaluated. The varieties showed varying response to Rhynchophorus ferrugineus Oliv; some varieties suffered heavy infestation while others indicated tolerance against R. ferrugineus. The most tolerant varieties with less infestation percentage against R. ferrugineus were Muzawati (8%) followed by Pathri (12%), Thothar (15%), Khar and Shakri (16%) respectively. The varieties which suffered high infestation rate were Karbalain, Dhedhi, Fasli, Aseel and Eidan Shah. To control the R. ferrugineus infestation pheromone trapping system was used. Significantly more R. ferrugineus (18-21) adults were captured during the 1 st , 2 nd , 3 rd week of July and 2 nd week of June. The studies conducted will be helpful in survey and control of R. ferrugineus infestation in Khairpur District of Sindh province.

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