Plasmodium vivax and Plasmodium falciparum are becoming resistant to drugs including antifolates, sulphonamides and chloroquine. This study was focused at sequence analysis of resistant genes of these parasites against sulphadoxine-pyrimethamine and chloroquine, from Bannu, Pakistan. Known mutations were detected at codons 57, 58 and 117 of pvdhfr gene of P. vivax, while none of the isolates had any pvdhps mutation. Similarly P. falciparum isolates exhibited double 59R + 108N mutations in pfdhfr, and single 437G in pfdhps thus demonstrating the existance of triple mutant 59R + 108N + 437G haplotype in this region. The key chloroquine resistance mutation, 76T in pfcrt was observed in 100% of the P. falciparum isolates, with haplotype SVMNT which is also associated with resistance to amodiaquine. Some novel mutations were also observed in pvdhfr and pfdhfr genes.

Background: The Bemisia tabaci is one of the most devastating pests of agricultural crops and ornamental plants worldwide. The genetic diversity and biotype status of the Bemisia tabaci in Pakistan was assessed by using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). A total 80 samples of B. tabaci collected from 14 districts of the Punjab province and 7 districts of the Sindh province were included. Results: All 10 primers screened in this study generated 151 scorable amplification products, of which 117 or 77% were polymorphic. Pairwise Nei and Li’s similarity had ranged from 0.25 to 0.88 among all individuals analyzed. Based on Nei and Li’s similarity coefficients Bemisia populations were grouped into 3 main clusters and clearly distinguished the non B biotype from the B biotype. Conclusion: The level of similarity among populations of same biotypes was high whereas between populations of non B and B biotypes appeared to be less closely related. This analysis showed that non B biotype is prevalent in both provinces however B biotype is restricted to few locations in Sindh. This monitoring of the spread of B. tabaci in Pakistan will assist in the establishment of appropriate management strategies.

Genetic diversity underlies the improvement of crops by plant breeding. Land races of rice (Oryza sativa L.) can contain some valuable alleles not common in modern germplasm. The aim here was to measure genetic diversity and its effect on agronomic traits among rice land-race genotypes grown in Pakistan. Diversity was measured using thirty-five microsatellite markers and seventy-five genotypes. Among the markers used a total of 142 alleles were detected at 32 polymorphic SSR loci, while three loci were monomorphic in Pakistani rice landraces. The number of alleles identified by each marker ranged from 2 to 13 with a mean of 4.4. Size differences between the smallest and largest alleles varied from 11bp to 71bp. Polymorphism information content ranged from 0.124 to 0.836, with an average of 0.569. At nine microsatellite loci, basmati-type landraces amplified more different alleles than those in the coarse-type. DNA markers RM70 and RM72 divided the rice landraces on the basis of days to flowering. A dendrogram based on total microsatellite polymorphism grouped 75 genotypes into four major clusters at 0.40 similarity coefficient, differentiating tall, late maturing and slender aromatic types from the short, early and bold non-aromatic ones. It inferred that Pakistani landraces have diverse genetic bases and can be utilized in future breeding programs. The DNA markers developed will assist in genotype identification, purity testing and plant variety protection.