Potato (Solanum tuberosum L.), an important food crop in the world, is susceptible to many fungal pathogens including Alternaria solani and Fusarium oxysporum causing Fusarium wilt and early blight diseases. Mycoparasitic fungi like Trichoderma encode chitinases, cell wall degrading enzymes, with high antifungal activity against a wide range of phytopathogenic fungi. In this study, a binary vector harboring endochitinase gene of ~1,000 bp was constructed and used to transform potato nodes through Agrobacterium-mediated transformation. Out of several primary transformants, two transgenic potato lines were verified for transgene insertion and integration by Southern blot. In a pot experiment for Fusarium resistance, the transgenic potato lines didn’t show any symptoms of disease, instead they remained healthy post infection. The transgenic potato lines exhibited 1.5 fold higher mRNA expression of endochitinase at 7 days as compared to 0 day post fungus inoculation. It was evident that the mRNA expression decreased over days of inoculation but was still higher than at 0 day and remained stable upto 30 days post inoculation. Similarly, for A. solani infection assay, the mRNA expression of the endochitinase gene was 3 fold higher 7 days post inoculation compared to expression at 0 day. Although the expression decreased by1.2 fold during subsequent days post infection, it remained stable for 30 days, suggesting that protection in transgenic potato plants against fungal pathogens was achieved through an increase in endochitinase transcript.
The future of food security in Africa is being severely threatened due to an exponential increase in population, which is almost three times the increase of food production. Maize production is constrained by stem borers which cause significant yield losses. Yield losses can be further compounded by higher temperatures due to climate changes, which are expected to increase the population of maize stem borers. While several methods have been employed in stem borer management, there is still significant damage caused by maize stem borers. This necessitates better control methods including the adoption of recent biotechnological advancement in RNA interference (RNAi) technology. This review highlights evidence of an increase in the stem borer population as well as the foreseen decline in maize production worldwide due to the effects of climatic changes. Furthermore, we have drawn attention to improved methods that have been used to control stem borers in maize production as well as a reluctant acceptance of traditional biotechnology in Africa. Finally, we suggest the application of alternative RNA interference techniques to breed maize for efficient pest control in order to achieve food security, improve nutrition and promote sustainable maize production.