6 research outputs found
Breeding for increased water use efficiency in chickpea
Water use efficiency (WUE) is a complex trait, hence secondary traits which are genetically associated with WUE and have a positive association with yield, easy to measure and have genetic variation can be used as breeding targets for high WUE. The aim of the present study was to discover the variation for water use efficiency and grain yield in different tillage and irrigation regimes; the basis of yield formation under water limited conditions and develop a chickpea ideotype. The field experiment was conducted at the Plant Breeding Institute, the University of Sydney in Narrabri, northwest New South Wales in Australia. A total of 36 entries were planted replicated twice under well-watered and water-stress conditions, and no-till and till regimes. Water use was monitored using a neutron probe moisture meter and water use efficiency calculated using the soil water balance method. Grain yield was higher under irrigation at 1722 kg/ha than rainfed conditions at 1478 kg/ha. No-till had 7.4% higher yield than the till regime. WUE was higher under no-till (5.02 kg/ha/mm) than under till (4.87 kg/ha/mm) and higher under irrigation (5.05 kg/ha/mm) than under rainfed conditions (4.84 kg/ha/mm). There was a strong association between grain yield and WUE under rainfed conditions, thus high yielding genotypes had high WUE. Sonali had the highest yield and WUE. Normalised difference vegetation index (NDVI) at early podding and late podding and chlorophyll content at late podding were useful marker traits in identifying genotypes with potentially high yield and high drought tolerance. Sonali, ICCV 96853 and PBA Slasher were identified as drought tolerant genotypes. The constructed chickpea ideotype had higher yields than the commercial varieties and had 76% resemblance to Sonali. By incorporating key target traits and targeting the right environment, chickpea yields can be sustained under soil water limited conditions
FAMILY DETERMINANTS OF TRANSITION FROM PRIMARY TO SECONDARY SCHOOLS IN MBOONI EAST DISTRICT, MAKUENI COUNTY, KENYA
Makueni County is affected by low transition rates, poor participation and completion rates. Access to secondary education in Mbooni-East district is also poor. The government of Kenya set a target of transition rate of 70% from primary to secondary schools from the current rate of 47%, and this is not achieved yet. The purpose of this study was therefore to investigate the family determinants of transition from primary to secondary schools in Mbooni-East district. Specifically this study sought to attain the following objectives: to establish the relationship between educational level of parents with transitions; determine the influence of parental income and transition; describe how the sibling position influenced transition and establish the measures which could be taken to enhance transition in the district. The results of this research were to generate useful information which would be used by educational planners and educational administrators to maintain efficient transitions in the district. Classical liberalism theory was used for the study. Descriptive survey research design was also used for this research as it was the most used method for collecting information on people’s attitudes, opinions, habits or any of the variety of educational or social issues. The study was conducted in secondary schools, in Kalawa division, Mbooni-East district, Makueni County. The target population was head teachers; Parents Teachers Association’s representatives (PTA’s) and all boys and girls in form one, in Kalawa division in the sampled schools. Probability sampling technique (systematic or interval sampling) was used because it removed the possibility of investigator bias. A sampling interval (k) and a random start were used to choose the sample. Research instruments were questionnaires for the head teachers, PTA’s and form ones and interview schedules for the PTA and the form ones in the division. Validity was done to check the accuracy of various skills and reliability done to determine the degree of coefficient of the theoretical concept. Piloting was done to check the accuracy of the research instruments. The questionnaires were filled and interview conducted in presence of the researcher at various different times. The data collected from the specific schools were analyzed through descriptive statistics. These are measures of central tendency such as the mean and percentages. The dependent variable was transition and the independent variables were parental level of education, parental income and sibling position on transition in Mbooni-East district. The findings showed a 45.6 percent of fathers’ who had reached form four and had a mean transition of 2.8 transition. Mothers’ who earned Kenya shillings 7500 formed 12.8 percent and a mean transition of 3.47. The results showed that transition was high to educated parents and low to illiterate parents, the sibling position favoured by transition were fifth borns who formed 20 percent and a mean transition of 2.8. Therefore, education is very necessary for the parents in order for them to educate their children; too, earning is also important for the parents in order to get money to educate their children. Lastly, every child should have equal opportunities to access secondary education, regardless of sibling position. Some measures which could be used to enhance transition in the district included building new schools and improving the existing ones, reduction of school fees and then government’s effort to sensitize the parents on the need and importance of supporting transition to all secondary schools in order to improve access to education in the district. Article visualizations
Chickpea Abiotic Stresses: Combating Drought, Heat and Cold
Chickpea is an important legume providing dietary proteins to both humans and animals. It also ameliorates soil nitrogen through biological nitrogen fixation. Drought, heat and cold are important factors among abiotic stresses limiting production in chickpea. Identification, validation and integration of agronomic, physiological and biochemical traits into breeding programs could lead to increased rates of genetic gain and the development of better adapted cultivars to abiotic stress conditions. This chapter illustrates the effects of stresses on chickpea growth and development. It also reviews the various traits and their relationship with grain yield under stress and proposes recommendation for future breeding
Evaluation of chickpea genotypes for resistance to Ascochyta blight (Ascochyta rabiei) disease in the dry highlands of Kenya
Chickpea (Cicer arietinum) is an edible legume grown widely for its nutritious seed, which is rich in protein, minerals, vitamins and dietary fibre. It’s a new crop in Kenya whose potential has not been utilized fully due to abiotic and biotic stresses that limit its productivity. The crop is affected mainly by Ascochyta blight (AB) which is widespread in cool dry highlands causing up to 100% yield loss. The objective of this study was to evalu- ate the resistance of selected chickpea genotypes to AB in dry highlands of Kenya. The study was done in 2 sites (Egerton University-Njoro) and Agricultural Training centre-ATC-Koibatek) for one season during long rains of 2010/2011 growing season. Thirty six genotypes from reference sets and mini-core samples introduced from ICR- SAT were evaluated. There were significant (P<0.001) differences in AB responses and grain yield performance in test genotypes in both sites. AB was more severe at Egerton-Njoro (mean score 5.7) than ATC-Koibatek (mean score 4.25), with subsequent low grain yield. Genotypes ICC7052, ICC4463, ICC4363, ICC2884, ICC7150, ICC15294 and ICC11627 had both highest grain yield in decreasing order (mean range 1790-1053 Kg ha-1) and best resist- ance to AB. Further evaluation is needed in other multi-locations and their use in breeding program determined especially because of their undesirable black seed color. Commercial varieties (LDT068, LDT065, Chania desi 1, and Saina K1) were all susceptible to AB, but with grain yield >1200 Kg ha-1. The findings of the study showed that chickpea should be sown during the short rains (summer) in the dry highlands of Kenya when conditions are drier and warmer and less favorable for AB infection. However yield could be increased by shifting the sowing date from dry season to long rain (winter) thus avoiding terminal drought if AB resistant cultivars with acceptable agronomic traits could be identified
Estimation of infection risk through airborne transmission in large open spaces with different air distributions
Respiratory diseases such as COVID-19 can be spread through airborne transmission, which is highly dependent on the airflow pattern of the studied room. Indoor air is typically not perfectly mixed even using a mixing ventilation, especially in large spaces. Airflow patterns in large open spaces such as hotel banquet rooms and open plan offices, are of particular concern, as these spaces usually accommodate more occupants and thus have the potential to spread diseases more rapidly leading to outbreaks. Therefore, understanding airflow patterns in large open spaces can help to estimate the detailed infection risk at certain locations in the space, which can prevent the spread of virus and track the potential new infections. This study estimated airflow patterns in a typical banquet room under theatre and banquet scenarios, and a large open plan office using computational fluid dynamics (CFD) simulations. Typical ventilation and air distribution approaches, as well as room layouts and occupant configurations in these scenarios were studied and applied in simulations. According to current results, the air distribution in a typical hotel banquet room with mixing ventilation can be very complicated, particularly for the banquet scenario. For a typical theatre scenario, under typical ventilation design, people sitting in the middle and lateral area were exposed to the highest infection risk. The front rows may be exposed to short-range transmission as well. For a banquet scenario, people sitting on the same table were more likely to be cross contaminated. But cross-table infection was still possible. The results can provide guidance on designing ventilation and air distribution approaches in large spaces with similar settings