The interactive relationship between the root–knot nematode Meloidogyne incognita and the root-rot fungus Macrophomina phaseolina in a root–rot disease complex of chickpea (Cicer arietinum var. avrodhi) was studied in a net house. The present study was carried out in such a manner so that the pathogenic potential of M. incognita and M. phaseolina individually, simultaneously and sequentially could be monitored. The pathogens singly as well as in combination led to significant reduction in growth, yield, nutrient and biochemical parameters. Gaseous exchange parameters like photosynthetic rate, transpiration rate and stomatal conductance were also reduced following infection of plants by the pathogens. However, maximum reduction was noticed in simultaneous inoculation with both pathogens. Sequential inoculation, where M. incognita preceded M. phaseolina by 15 days, was more damaging to the crop in comparison to that where M. phaseolina preceded M. incognita inoculation by 15 days. Infection by M. phaseolina caused a considerable reduction in the number of galls, egg–masses and nematode multiplication, with the highest reduction observed in plants simultaneously inoculated with the pathogens. Those plants also showed the highest disease severity in terms of percent root–rot. Thus, a manifold action plan to reduce the impact of the root-rot disease complex on chickpea crops has to be formulated.
A.M. Khan, S. Fiaz, I. Bashir, S. Ali, M. Afzal, K. Kettener, N. Mahmood and M. Manzoor
Nine cotton genotypes, comprised of four non Bt males (CIM-1100, CIM-506, FH-942 and FH-900), five Bt female genotypes (FH-113, FH-114, MNH- 886, AA-703 and IR-3701) and their 20 crosses were screened in order to evaluate their response to Cotton leaf curl virus symptoms through epidemiology in the field and greenhouse. The 20 crosses among their nine parents were sown in two replications under randomized complete block design, during 2013 and 2014. The mean squares were significant for all traits indicating that both additive and non-additive genes control the characters, but non-additive genes were more important because, variance of dominant genes were higher than additive genes. In our test, FH-900 showed the best performance against CLCuV, number of lobes per boll and seed yield. The CIM- 1100 genotype performed well in boll weight, fiber strength and fiber fineness, whereas CIM-506 was good for plant height, number of sympodial branches and ginning. Maximum boll number, seed index and fiber length were shown by FH-942. Among lines, MNH886, FH-113, IR-3701 and FH-114 exhibited the best general combination for many traits. Hence, parents were preferred for hybridization program to improve the majority of characters. Hybrids FH-113 × FH-942, MNH-886 × CIM-1100, MNH-886 × FH-942, IR-3701 × CIM-506, AA-703 × CIM-1100, FH-114 × FH-942, FH-114 × CIM-1100 and MNH-886 × FH- 900 was best in specific combinations for different traits, especially against CLCuV. The results indicated that to increase resistance against CLCuV, hybrids should be exploited to develop CLCuV resistance.
H.A. Wajid, A.A. Alderfasi, I. Afzal, M.B. Junaid, A. Mahmood, A. Ahmad, M.N. Arsal and M.U. Tahir
The present research was conducted under laboratory conditions. The purpose of research was to investigate the potential of priming with press mud, peat moss, sand, gunny bags, compost, farm yard manure and moringa leaf extract (MLE) on seedling growth and germination capacity of maize seed. Untreated or non-primed seeds were used as a control treatment. Priming treatments improved germination capacity, stand establishment and seedling vigor, compared with control. Priming with moringa leaf extract enhance germination and seedling vigor of maize seed, compared with the control and other seed primed treatments. In moringa leaf extract primed seeds, root and shoot growth was improved. Overall, moringa leaf extract primed maize seeds performed better than all other treatments and it could be related by seedling vigor enhancement and lowering the mean germination time, due to imbibition of higher quantity of water and earlier enzymatic activity. The results propose that moringa leaf extract priming treatment had the potential to enhance germination, stand establishment and early growth of maize seeds.