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Cotton is considered as a major cash crop of the world. It earns huge foreign exchange by its valuable products; fiber, lint, cotton seed oil, hull and a lot more. Being an important fiber crop, it earns huge foreign exchange by contributing to textile and seed oil industry. This review summarizes cotton biology, its diversity and domestication, genome assembly, constraints in its production and methods to improve cotton plant to fulfill the need of textile and oil industry. But cotton is facing enormous biotic and abiotic stresses with insect pests being most prominent. Massive destruction caused by insects needs to be controlled for maintaining fruitful cotton crop production. Conventional breeding approaches are limited to improving single trait and integrate stable genes within plant genome in approximately 7 - 8 years. Improved biotechnological procedures have paved new pathways to target genes specifically and improve cotton germplasm in lesser time than conventional breeding.

Genome editing is considered as the most widely used approach of the present era. It had become a basic need of the current micro and molecular biological experiments. Gene engineering finds its widespread applications in medical, industry and agricultural sector. Unlike previous genetic engineering practices to insert or delete a part of genetic material at random place, genome editing allows the precise manipulation of DNA at a specific location. Zinc Finger Nucleases (ZFNs), Transcription Activator like Effector Nucleases (TALENs), Clustered Regularly Interspresed Short Palindromic repeats (CRISPR/Cas system) and meganucleases (recombinases) are the prime tools for editing an organism’s genome. Genome editing tools have an advantage to selectively delete or to integrate specific genes at specific loci. Use of recombinases for specifying site has further reduced time to integrate genes site specifically. Site specific gene stacking by the use of recombinases coupled with ZFNs, TALENs, or CRISPR/Cas genes have paved new pathways to target genes site specifically and to improve germplasm in lesser time than conventional breeding approaches.

The international recognition of the importance of genetic diversity demands continuous estimation of genetic diversity of in hand population as test of its buffering capacity against all putative threats. Randomly selected Pakistani wheat varieties developed during 1965-1999 and 2000-2011 were evaluated on the basis of pedigree and SSR data. At 2nd and 3rd levels of pedigree, average occurrence of a parent per variety was 2.1 times. The dominating parents included BLUEBIRD, KALYANSONA and SIETE-CERROS-66, which were present in the pedigrees of 71.42%, 64.28%, and 58.57% varieties, respectively. The varieties INQLAB-91 and KIRAN-95 had the same pedigree and were genetically identical as revealed by SSR data. Similarly, varieties PAVON-76 and SOGHAT-90 also had the same parents in their pedigrees. This genetic similarity was also confirmed by SSR based cluster. The SSR based PC1 and PC2 showed narrow genetic diversity confirming the presence of few dominating parents. The results emphasize the inclusion of novel and genetically diverse parents in Pakistani wheat breeding programs to maintain broader genetic base of varieties/cultivars for buffering the effects of ever changing virulent pathogens and crop growth environments.