Classification of stress tolerant cotton genotypes is a challenge for breeders and physiologists. In quantitative genetics, diallel analysis is a mating design used to identify superior genotypes for hybridization and selections programmes. Twelve popular cotton cultivars viz., ‘CRIS-134’, ‘CRIS-342’, ‘Sadori’, ‘Chandi’, ‘Sindh-1’, ‘NIAB-78’, ‘CIM-496’, ‘CIM-499’, ‘CIM-506’, ‘CIM-534’, ‘BH-160’ and Bt-cotton (Australian origin) were screened at seedling and reproductive stages and six genotypes such as CRIS-134, Sadori, Sindh-1, CIM-496, CIM-506 and CIM-534 were recognized as reasonably drought tolerant based on developmental, yield, fibre and physiological characters. For further confirmation of drought tolerant cotton genotypes, fourteen drought tolerance indices based on various mathematical approaches were applied. When comparing twelve cotton varieties on only yield basis, high and positive correlation (r=0.66**) between the yield in drought stress (Ys) and yield in water stress conditions (Yp) suggested that majority of the varieties performed similar in both the environments. Out of twelve, six genotypes such as CRIS-134, Sadori, CIM-496, Sindh-1, and CIM-506 produced higher seed cotton yields both in non-stress and in water stress, hence these genotypes were declared as drought tolerant. Through 6 x 6 half diallel diallel mating fashion, 15 F1 hybrids were developed for genetic analysis. The experiments were carried-out in factorial design with two irrigation regimes (non-stress and water stress at reproductive stage) in four replications at experimental field, Department of Plant Breeding and Genetics, Sindh Agriculture University, Tandojam during 2009 to 2011. The yield, fibre and physiological traits were consisted of bolls opened at 110 days after planting, plant height (cm), sympodial branches plant-1, bolls plant-1, boll weight (g), seed cotton yield plant-1 (g), seed cotton yield (Kg ha-1), lint%, seed index (g), staple length (mm), fibre strength (tppsi), leaf area, relative water content (%) and stomatal conductance (mmol m-2s-1). In screening experiments, at developmental and reproductive stages of crop, water stress significantly affcteted shoot length, root length, number of lateral roots, leaf area, relative water content, excised leaf water loss, stomatal conductance, and stomatal density. The significance of treatments x genotypes interactions revealed that cotton cultivars performed variably over irrigation regimes. The significance of mean squares for general combining ability (GCA) and specific combining ability (SCA) for most of the characters under water stress and normal irrigation indicated that both additive and non-additive genes were equally important in advocating the characters studied. However, in stress imposed at reproductive phase, the SCA variances were higher than GCA for plant height, boll weight, seed index, leaf area, relative water content and stomatal conductance indicating the predominance of dominant genes for these traits. Nonetheless, GCA variances were greater for other traits such as bolls opened at 110 days after planting, sympodia plant-1, bolls plant-1; seed cotton yield kg ha-1, lint%, staple length and fibre strength and such results indicated predominance of additive genes advocating the above characters. The parents CRIS-134, Sadori, and CIM-534 with higher GCA estimates proved as good general combiners for hybridization and selection programmes so as to evolve novel moisture stress tolerant breeding material. From hybrids, crosses Sadori x Sindh-1, CRIS-134 x Sadori, CIM-496 x CIM-534, Sadori x CIM-534 and CIM-496 x CIM- 534 by expressing higher SCA effects for majority of traits were considered as good specific combiners, thus they are suitable for hybrid cotton development for both stress and non-stress environments. From 15 hybrids evaluated, five potential hybrids such as Sadori x CIM-534, Sadori x Sindh-1, CIM-496 x CIM-534, Sadori x CIM-534 and CRIS-134 x CIM-496 manifested higher heterotic effects and high SCA estimates for majority of traits under stress are suitable combinations for hybrid cotton development. Three types of gene interactions such as additive x additive, additive x non-additive and non-additive x non-additive were involved in the manifestation of higher heterosis in the above hybrids based on GCA estimates of parents involved in above particular hybrids. The broad sense heritability estimates in stress conditions were, by and large, greater than in non-stress environment such results indicated that yield, fibre and physiological traits are mainly advocated by the additive genes; hence selection would be rewarding to improve studied traits for drought tolerance in earlier segregating generations. The narrow sense heritability estimates were far lower than broad sense heritability in either non-stress or in water stress conditions and such results suggested that selection in later segregating generations may be more successful. The combined correlation coefficients (r) determined from pooled data of parents and their F1 hybrids revealed that by and large, the correlations were higher in moisiture stress than in non-stress environment. In stress conditions, the high positive association between yield, fibre and physiological traits suggested that plant height, sympodia plant-1, bolls plant-1, boll weight, seed cotton yield, lint%, staple length, fibre strength were significantly and positively correlated with leaf area, relative water content, yet all these traits were negatively correlated with only stomatal conductance. These positive correlations indicated that more than one trait can be used as selection criteria to aid selection process under water stress conditions.
Parental factors impact students’ self-concept and academic performance during the pandemic. Thus, this study determined the students’ self-concept and academic performance and the parental factors related to it. The research design was descriptive-correlational, and 500 nonrandom college students in West Philippines participated in the study. Researcher-made instruments were used, which were subjected to reliability and validity evaluation. Data were collected online from June 2021 to July 2022 and were analyzed using descriptive (frequency counts and percentage) and inferential statistics (Spearman correlation). Results revealed a positive self-concept and satisfactory academic performance among the students. Besides, parental factors such as educational attainment and school/classroom involvement are significantly related to self-concept and academic performance. Further, self-concept is significantly associated with academic performance. This shows that some parental factors are vital in developing the student’s self-beliefs and supporting their studies and academic endeavors amid the COVID-19 pandemic. Future studies may consider more factors related to academic achievement and self-concept. Other researchers may find the mediation or moderation effect of self-concept between parental factors and students’ scholastic achievement.
KEYWORDS: academic performance, COVID-19 pandemic, distance learning, higher education, parental factors, self-concept
In the Pakistani society, leadership is considered as a male attribute, as it is associated with the masculine traits such as authority and control. This assumption not only affects women's entry into leadership positions, but it also affects men who opt for this position, as they are expected to behave in a way that is considered masculine. However, current leadership theories demand leaders to be more collaborative and caring and possess people-oriented traits that are commonly associated with women. Literature on leadership in Pakistan are silent about whether male and female school leaders lead their schools in similar or different ways. This study sought to explore the similarities and differences in leadership styles of a male and a female head teacher. The study employed a case study approach. Information was gathered through individual interviews, focus group interviews, document analysis and observations. One male head teacher and one female head teacher from private secondary schools in Karachi were the primary participants of the study. Four teachers and four students from each school were interviewed to find out their views about their head teachers, data were triangulated from gathering their head teachers' views and from other sources like document analysis and observation. The findings of the study suggest that the male head teacher and the female head teacher exhibit similar styles of leadership. They execute a combination of leadership styles according to the demand of the situation and these range from transactional to transformational styles of leadership. The data evidenced that both the head teachers emphasized on teaching and learning process in their schools. They have developed a learning environment not only for the students but also for the teachers. They have delegated power and authority to the staff and the students. The findings also suggest that leaders are not born but they are developed, as various factors are involved in enhancing their leadership skills and knowledge: training programs, availability of role models, socialization and experiences of being led by others. The study makes several recommendations: i) the need to re-culture the stereotyping associated with the notion of leadership and leadership positions and ii) providing head teachers with an opportunity to access training programs to develop their skills as leaders.