<i>‘What retention’ means to me</i>: the position of the adult learner in student retention

Studies of student retention and progression overwhelmingly appear adopt definitions that place the institution, rather than the student, at the centre. Retention is most often conceived in terms of linear and continuous progress between institutionally identified start and end points. This paper reports on research that considered data from 38 in-depth interviews conducted with individuals who had characteristics often associated with non-traditional engagement in higher education who between 2006 and 2010 had studied an ‘Introduction to HE’ module at one distance higher education institution, some of whom had progressed to further study at that institution, some of whom had not. The research deployed a life histories approach to seek a finer grained understanding of how individuals conceptualise their own learning journey and experience, in order to reflect on institutional conceptions of student retention. The findings highlight potential anomalies hidden within institutional retention rates – large proportions of the interview participants who were not ‘retained’ by the institution reported successful progression to and in other learning institutions and environments, both formal and informal. Nearly all described positive perspectives on lifelong learning which were either engendered or improved by the learning undertaken. This attests to the complexity of individuals’ lives and provides clear evidence that institution-centric definitions of retention and progression are insufficient to create truly meaningful understanding of successful individual learning journeys and experiences. It is argued that only through careful consideration of the lived experience of students and a re-conception of measures of retention, will we be able to offer real insight into improving student retention

Sorghum Improvement for Semi-Arid Tropics Region : Past Current and Future Research Thrusts in Asia

Sorghum Is widely grown in the Semi-Arid Tropics (SAT) for food, feed, fodder arid forage. Although India and Africa represent the major sorghum growing areas, grain yield levels are low compared to those in the developed world. An attempt Is made to summarize the relevant research thrusts that have implications on Improving sorghum genetically. The cultivated taxa, Sorghum bico lo r (L.) Moench with 2n = 20 were evolved and domesticated in North Eastern Africa. Based on spikelet characters, they are grouped into five racescaudatum, guinea, kafir, durra and bicolor and ten hybrid races. The cultivated forms probably arose from S. verticihiflorum. Nearly 35000 landraces collected from 87 countries are being maintained at ICRISAT Asia Center, Hyderabad, India. - Initial attempts to breed sorghum were in understanding inheritance of several morphological traits based on mendelian factors and breeding for specific adaptation. The establishment of All India Coordinated Sorghum Improvement Project in 1970, and International Crops Research Institute for the Semi-Arid Tropics with sorghum as one of its mandate crop in 1972 and the initiation of conversion program in USA in early part of 1960s demonstrated that wide adaptability and high yield can be combined and also produced materials which contributed well to several national programs in the SAT. Recurrent selection methods adopted with the help of genetic male sterile genes were not as effective as pedigree/backcross methods to achieve high yield. Discovery of genetic-cytoplasmic male sterility in 1954 enabled hybrid seed production cost effective, and it was established soon that hybrids were superior to varieties across all ranges of environments. Several high yielding hybrids were produced and released. Soon, lack of resistance to various yield constraints was recognized. Current research portfolios involve breeding of male-sterile and restorer lines in diversified cytoplasmic background for resistance to various yield constraints with high grain fodder yield. The goal is to produce high yielding resistant cultivars. Future strategies of sorghum improvement for SAT is encoded in ICRISAT's Medium Term Plan which recognized a total of 29 production systems, five adaptation zones, and a multidisciplinary research strategy of producing high yielding resistant parents, and developing integrated pest, diseases, soil and water management methods

A Role For Icrisat In Enhancing And Maintaining Genetic Resources On-Farm

CGIAR centers have made a major global contribution to ex situ conservation of crop genetic resources. Some centers have also made detailedsocio-anthropologicaIstudies ofmanda'te crops in traditional farmingsystems and, more recently, farmerparticipatory research is becoming part of crop irnprovementprograrns. Centers can expand these studies to develop strategies for on-farm conservation in close collaboration will) nalional agricultural research and extension systems, NGOs and farmers. A specific role for ICRISAT is firmly based on its locations in centers of crop diversity and traditional agriculture; its complement of experienced crop scientists and extensive databases; ils capacityto analyzegenetic, environmental, andgenotypexenvironmentinteractions as determinants of crop productivity; its close relalionships with netionalprograms; anditsgrowing involvement in farn~erparticipato ry research, The expertise and experience of lCt7lSA Tand other CGlAR centers can make a major contribution to the dynamic conservation, enhancement and utilization of agrobiodiversity on-farm for tl~bee nefits of farmers and global foodproduct/on

Sorghum grain hardness and its relationship to mold susceptibility and mold resistance

Sorghum [Sorghum bicolor (L.) Moench] cultivars exhibiting contrasting reactions to the gram mold complex were grown at Patancheru, India, in one postrainy (1988-1989) and two consecutive rainy seasons (1989 and 1990). Sorghum grain hardness was measured by four methods: grinding time required to obtain a fixed volume of flour from grains in a Stenvert hardness tester, force required to break the grains using Kiya and Instron food testers, and density grading in sodium nitrate solution measured as percentage of floating grains. Ergosterol concentration was determined in grains to assess the extent of mold damage. The Stenvert method was convenient and rapid and was significantly correlated with the other three methods but negatively and significantly correlated with the ergosterol concentration. Grains grown in the postrainy season exhibited higher hardness than those grown in the rainy seasons. Mold-resistant cultivars exhibited significantly greater hardness than mold-susceptible cultivars. Ergosterol concentration indicating the extent of mold attack was negatively and significantly( P < 0.01) correlated with Stenvert hardness values in mold-resistant phenotypically white sorghum grains (without testa) in both the rainy seasons

Genetic analysis of grain mold resistance in white seed sorghum genotypes

Grain molds in rainy season sorghums can cause poor grain quality resulting in economic losses. Grain molds are a major constraint to the sorghum production and for adoption of the improved cultivars. A complex of fungi causes grain mold. Information on genetics of grain mold resistance and mechanisms is required to facilitate the breeding of durable resistant cultivars. A genetic study was conducted using one white susceptible, three white resistant/tolerant sources, and one colored resistant source in the crossing programme to obtain four crosses. P1, P2, F1, BC1, and BC2, and F2 families of each cross were evaluated for the field grade and threshed grade scores, under sprinkler irrigation. Generation mean analyses and frequency distribution studies were carried out. The frequency distribution studies showed that grain mold resistance in the white-grained resistance sources was polygenic. The additive gene action and additive × additive gene interaction were significant in all the crosses. Simple recurrent selection or backcrossing should accumulate the genes for resistance. Epistasis gene interactions were observed in colored resistance × white resistance cross. Gene interaction was influenced by pronounced G × E. Pooled analysis showed that environment × additive gene interaction and environment × dominant gene interaction were significant. The complex genetics of mold resistance is due to the presence of different mechanisms of inheritance from various sources. Evaluation of segregating population for resistance and selection for stable derivatives in advanced generations in different environments will be effectiv

Genetic analysis of grain mould resistance in coloured sorghum genotypes

Grain moulds are a major constraint to sorghum production and to adoption of improved cultivars in many tropical areas. Information on the inheritance of grain mould reaction is required to facilitate breeding of resistant cultivars. The genetic control of grain mould reaction was studied in 7 crosses of 2 resistant sorghum genotypes. P1, P2, F1, F2, BC1 and BC2 families of each cross were evaluated under sprinkler irrigation for field grade and threshed grade scores and subjected to generation mean analysis. Frequency distributions for grain mould reaction were derived and F2 and BC1 segregation ratios were calculated. Grain mould reaction in crosses of coloured grain sorghum was generally controlled by two or three major genes. Resistance to grain moulds was dominant. Significant additive gene effects were also found in all cross/season combinations. Significant dominance effects of similar magnitude to additive effects were also observed in five out of ten cross/season combinations. Gene interactions varied according to the parents with both resistant and susceptible parents contributing major genes. Choice of parents with complementary resistance genes and mechanisms of resistance will be critical to the success of resistance breeding

Variation in inheritance of resistance to sorghum midge, Stenodiplosis sorghicola across locations in India and Kenya.

Sorghum midge [Stenodiplosis sorghicola (Coquillett)] is an important pest of grain sorghum, and host plant resistance is one of the important components for the management of this pest. We studied the inheritance of resistance to this insect involving a diverse array of midge-resistant and midge-susceptible genotypes in India and Kenya. Testers IS 15107, TAM 2566, and DJ 6514, which were highly resistant to sorghum midge in India, showed a greater susceptibility to this insect in Kenya. The maintainer lines ICSB 88019 and ICSB 88020 were highly resistant to sorghum midge in India, but showed a susceptible reaction in Kenya; while ICSB 42 was susceptible at both the locations. General combining ability (GCA) effects for susceptibility to sorghum midge for ICSA 88019 and ICSA 88020 were significant and negative in India, but such effects were non-significant in Kenya. The GCA effects of ICSB 42 for susceptibility to sorghum midge were significant and positive at both the locations. The GCA effects were significant and positive for Swarna, and such effects for IS 15107 and TAM 2566 were negative at both the locations. GCA effect of DJ 6514 were significant and negative in India, but non-significant and positive in Kenya; while those of AF 28 were significant and positive during the 1994 season in India, but significant and negative in Kenya. Inheritance of resistance to sorghum midge is largely governed by additive type of gene action. Testers showing resistance to sorghum midge in India and/or Kenya did not combine with ICSA 88019 and ICSA 88020 to produce midge-resistant hybrids in Kenya. Therefore, it is essential to transfer location specific resistance into both parents to produce midge-resistant hybrids

Using digital time-lapse cameras to monitor species-specific understorey and overstorey phenology in support of wildlife habitat assessment

Critical to habitat management is the understanding of not only the location of animal food resources, but also the timing of their availability. Grizzly bear (Ursus arctos) diets, for example, shift seasonally as different vegetation species enter key phenological phases. In this paper, we describe the use of a network of seven ground-based digital camera systems to monitor understorey and overstorey vegetation within species-specific regions of interest. Established across an elevation gradient in western Alberta, Canada, the cameras collected true-colour (RGB) images daily from 13 April 2009 to 27 October 2009. Fourth-order polynomials were fit to an RGB-derived index, which was then compared to field-based observations of phenological phases. Using linear regression to statistically relate the camera and field data, results indicated that 61% (r 2?= 0.61, df = 1, F?= 14.3, p?= 0.0043) of the variance observed in the field phenological phase data is captured by the cameras for the start of the growing season and 72% (r 2?= 0.72, df = 1, F?= 23.09, p?= 0.0009) of the variance in length of growing season. Based on the linear regression models, the mean absolute differences in residuals between predicted and observed start of growing season and length of growing season were 4 and 6 days, respectively. This work extends upon previous research by demonstrating that specific understorey and overstorey species can be targeted for phenological monitoring in a forested environment, using readily available digital camera technology and RGB-based vegetation indices

Compensation in grain weight and volume in sorghum is associated with expression of resistance to sorghum midge, Stenodiplosis sorghicola

Sorghum midge, Stenodiplosis sorghicola (Coquillett) is one of the most important pests of grain sorghum worldwide. We studied the inheritance of resistance to sorghum midge and compensation in grain weight and volume in panicles of sorghum hybrids and their parents under uniform infestation (40 midges per panicle for two consecutive days). Sorghum midge damage ranged from 8.2 to 82.4% in the maintainer lines (B-lines) of the females parents (A-lines), and 9.0 to 67% in the male parents (restorer lines). Hybrids involving resistant × resistant parents were highly resistant, while those involving resistant × susceptible and susceptible × resistant parents showed moderate susceptibility. Susceptible × susceptible hybrids were susceptible. Compensation in (percentage increase) grain weight and volume in midge-infested panicles of midge-resistant parents and their F1 hybrids was greater than in midge-susceptible parents and hybrids. General combining ability effects for midge damage, and grain weight and volume were significant and negative for the midge-resistant females (ICSA 88019 and ICSA 88020), whereas those for the midge-susceptible females (ICSA 42 and 296 A) were significant and positive. However, the reverse was true in case of compensation in grain weight and volume. Inheritance of compensation in grain weight and volume and resistance to sorghum midge is controlled by quantitative gene action with some cytoplasmic effects. Resistance is needed in both parents to realize full potential of midge-resistant hybrids

Gene action for resistance in sorghum to midge, Contarinia sorghicola

Gene action for resistance to sorghum midge (C. sorghicola [Stenodiplosis sorghicola]) was studied in a diverse array of midge-resistant and midge-susceptible females and males under natural infestation and under uniform infestation with a no-choice headcage technique. Gene action for glume and grain characteristics associated with resistance to sorghum midge was also studied to understand their role in expression of resistance to this insect. Gene action for resistance to midge is largely governed by additive gene action. Genotype × environment interaction was significant for midge damage rating under natural infestation, but non-significant under no-choice headcage screening. The GCA effects of midge-resistant CMS females (PM7061A and PM7068A) were significant and negative, and such effects for the midge-susceptible CMS females ICSA42 and 296A were positive. Similar results were observed for the males (except for CS3541 and MR750 for midge damage in one out of two seasons). Dominance (mid-parent heterosis) was also important for midge resistance in some cross combinations. For genotypic non-preference by the midge females, the SCA effects were greater than the GCA effects. The SCA effects for genotypic non-preference were negative for PM7061A. The GCA effects were significant and negative for glume length in PM7061B, glume hardness for 296B, and glume hairiness for PM7061B. The GCA effects were significant and positive for glume length, glume hairiness and glume hardness of ICSB42. Resistance is needed in both the parents to produce midge-resistant hybrid