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Common bean production is constrained by different diseases the major ones being, Angular Leaf Spot (ALS), bean root rot, anthracnose, Common Bright Bacteria (CBB), Bean Common Cosaic Virus (BCMV) and Bean Common Mosaic Necrotic Virus, (BCMNV). The aim of this study was to identify new and better sources of broad resistance to both bean ALS and Root Rot diseases among nutritional bean varieties. Fifty seven varieties were planted in the screen house of CIAT Africa based at Kawanda Agricultural Research Laboratories Institute (KARL). Virulent inocula actually used at CIAT were used to test these genotypes. Different varieties were resistant to specific isolates but interestingly, only ACC 714 contained broad resistance to both Andean and MesoAmerican isolates of bean Angular Leaf Spot as well as Fusarium root rot and Pythium root rot at mean, median and mode basis. Since different nutritional bean varieties have varying levels of resistance to different pathogens, it may be possible to pyramid these resistance genes into appropriate background so as to provide durable resistance in biofortified bean genotypes higher in iron and zinc content.

Snap bean (Phaseolus vulgaris) is a potential income earner for subsistence farmers in Rwanda. The crop realises a higher income per unit dry weight than dried beans. Constraints of pests and the problems of pesticide use call for alternatives that are safer for consumers. The objective of the study was to evaluate the effects of neem, tephrosia, tobacco and cow urine on pest infestation and yield of snap bean in Rwanda. The treatments were sprays of leaf extracts of neem, tephrosia, and tobacco, cow urine, and a control (water). The treatments were replicated four times in a randomized complete block design. Biopesticide and water applications and insect counts were carried out every one and a half to two and a half weeks. Insect counts were done on a sample of 10 or 20 plants. All whiteflies observed on whole plants were counted. Aphids were counted on a randomly selected shoot while all thrips found on a random sample of five leaves or flowers were counted. Yield data (fresh weight) per hectare was calculated from the middle rows of each plot, leaving out the border rows. Insect counts were totaled across the season for analysis. Major pest species observed were whitefly (Bemisia tabaci), black bean aphid (Aphis fabae), and thrips. In the first season, the number of whiteflies was not significantly different among treatments. The tobacco treatment resulted in a significantly lower number of aphids than all other treatments. The lowest populations of thrips were observed in plots treated with neem and tephrosia. The cow urine treatment gave the highest total and marketable yield. In the second season, tephrosia treatments significantly reduced populations of thrips. However, total and marketable yield were not significantly different among the treatments. It is concluded that tobacco has potential for control of aphids while neem and tephrosia could be used to control thrips. The insect populations attacking snap bean were probably too low to influence yield. However, differences observed in populations of aphids and thrips may translate into differences in yield in seasons when insect populations are high.

The success of contemporary breeding programmes involving genetic engineering depends on the stability of transgene expression over many generations. We studied the stability of transgene expression in 40 independent rice plant lines representing 11 diverse cultivated varieties. Each line contained three or four different transgenes delivered by particle bombardment, either by cotransformation or in the form of a cointegrate vector. Approximately 75% of the lines (29/40) demonstrated Mendelian inheritance of all transgenes, suggesting integration at a single locus. We found that levels of transgene expression varied among different lines, but primary transformants showing high-level expression of the gna, gusA, hpt and bar transgenes faithfully transmitted these traits to progeny. Furthermore, we found that cry1Ac and cry2A transgene expression was stably inherited when primary transformants showed moderate or low-level expression. Our results show that six transgenes (three markers and three insect-resistance genes) were stably expressed over four generations of transgenic rice plants. We showed that transgene expression was stable in lines of all the rice genotypes we analysed. Our data represent a step forward in the transfer of rice genetic engineering technology from model varieties to elite breeding lines grown in different parts of the world.

Environmental and biotic stresses, such as drought, low fertility, diseases and weeds, are causing annual losses of million tons of maize grain in sub-Saharan Africa. The utilization of drought tolerant, extra-early maturing, disease and insect resistant maize varieties with Nitrogen Use Efficiency (NUE), has boosted maize production in areas where drought and disease are severe. Experiments were conducted with the objective of identifying suitable maize varieties for the mid-altitude environment that are tolerant to drought and resistant to infestations of Maize Streak Virus (MSV) and Turcicum Leaf Blight (TLB). The experiments were conducted in four sites (Rubona, Bugarama, Nyagatare, Karama) in Rwanda during the 2009 B and 2010 A seasons. They consisted of nine new hybrid varieties, seven new open pollinated varieties (OPVs), one hybrid check and four OPV checks. The AMMI (Additive Main Effects and Multiplicative Interaction) model for grain yield was used to analyse data. It showed that grain yield variation due to environments, genotypes and Genotype by Environment Interaction (GEI) was highly significant (p < 0.01). However, genotype effects accounted for 53 % of the sums of squares of treatments while environment accounted for 31 % and GEI effects for 16 %. The AMMI 1 biplot showed that drought tolerant and extra-early maturing cultivars were the most stable across environments. The AMMI 2 biplot showed that two OPVs were the least sensitive to the changes in the environments, and harsh environments exerted strong interactive forces on genotypes. Analysis of AMMI 1 and AMMI 2 biplots allowed six elite cultivars to be identified for the mid-altitudes which were stable across environments —CML442/CML440//CML445 (9.77 t/ha), CML312/CML202//CML445 (8.79 t/ha), CML144/CML159//CML182 (8.02 t/ha), NYA1 (Pop Nyag) (8.70 t/ha), RUB2 (DTLWN1) (7.99 t/ha) and ECA_EPOP1 (5.88 t/ha). The hybrid variety CML442/CML440//CML445 was drought tolerant, hence it was suitable for the semi-arid mid-altitudes; the hybrid cultivar CML312/CML202//CML445 combined resistance to MSV and TLB. The hybrid variety CML144/CML159//CML182 was a Quality Protein Maize (QPM). The OPV NYA1 combined several traits including earliness, resistance to foliar diseases and tolerance to drought. The variety RUB2 had desirable grain quality in addition to resistance to foliar diseases. Variety ECA_EPOP1 was extra-early and attained full maturity in 100 days after planting.

Climbing beans provide the best option for intensification and the production of surplus beans in Rwanda where arable landholdings are diminished. Shortage of staking wood is a major challenge limiting the wider adoption of the crop. Poor staking or none causes a yield loss of 50–90 %. Due to wood scarcity, this study was undertaken to evaluate feasible and farmer-acceptable innovations that avoid over-reliance on the wood staking while maintaining yield benefits. Six densities at 0 (zero staking), 15,000; 16,670; 20,000; 23,000 poles with trellises and 50,000 poles without trellises/ha−1 (normal practice) were used to stake adapted varieties ISAR-CB-105 (MAC 9) or ISAR-CB-102 (RWV 1129) in a randomized complete block design (RCBD) at six locations: Muhanga, Rubona, Rwerere, Nyagatare, Ngoma and Karama over three seasons in 2009 and 2010. Farmers’ preferences for the staking innovations were assessed for the various treatments at physiological maturity growth stage of the crop. Grain yield differences across the treatments were determined by performing analysis of variance (ANOVA) using R- Statistical package. Total grain yields ranged from 180 to 6,200 kg/ha with means from 1,730 to 3,120 kg/ha The lowest value was observed in the zero-staked treatment (control) and the highest in 100 % wood staked (50,000 without trellises). Fully staked plots also produced the highest yields by 87 % across sites and seasons. However, the differences in mean grain yields were statistically insignificant at P(0.001–0.005) between all treatments except for the zero-staked plots where it was significantly lowest. Most farmers (92 %) preferred combinations of 16,670 wood stakes/ha with trellises that reduced the wood requirement by 67 % with a minimal reduction in yield of 6 % of the normal practice control. The fully wood staked treatment ranked fifth with 25 % preference and the zero-staked treatments ranked sixth (last) with 8 % preference. Although a gain in grain yield was important, farmers’ choices depended most on the envisaged availability, labour implication, durability and cost of stakes. Selection criteria were segregated by gender. Environmental concerns were mentioned but featured least. Therefore, although the highest staking density maximized yields, it was viewed as the biggest challenge, especially among women farmers who were, in turn, most comfortable with the use of trellises. A strategic combination of stakes with trellises that caused the maximum reduction of the number of wooden poles and the minimum loss of grain yield benefits/unit area was the most acceptable option to overcome this challenge. Further study to provide empirical evidence of the cost–benefits of the different staking innovations is underway.

Agricultural research is the engine driving agricultural growth in Rwanda which has resulted in the country being food secure over the last two years (2010–2011). Research has developed and released high yielding, disease and pest resistant crop varieties, animal breeds/genotypes and other improved technologies. These have resulted in increased productivity/unit area while protecting the natural resource base. In line with national policies, combating malnutrition and extreme poverty has also been a priority for agricultural research. This paper highlights the different components of research responsible for the observed growth in the sector in Rwanda over the period from 2001 to 2011. This information could be useful to other countries in the region pursuing similar goals of improving food production for their populations.

About 200 Million people in the world suffer from hunger. The United Nations (2007) estimates that the world population will reach 8.1 Billion people by 2030. Meeting global food requirements will necessitate increasing food production by 50%. The most attractive strategy to meet this challenge is to increase smallholder agricultural productivity. This strategy will not only increase food supply, it will also increase smallholder incomes, reduce malnutrition and improve livelihoods of the poor. Biotechnology has the potential to increase the world’s food output and reduce food insecurity. Plant biotechnology offers a wide scope of possibilities for increasing productivity, diversification and development of a more sustainable agriculture. This technology includes biopesticide production, plant tissue culture techniques, and the use of advanced molecular biology techniques for plant transformation, genomic analysis coupled with breeding and plant disease diagnoses. Agricultural biotechnology will contribute to food security through technologies that improve yield and quality and can easily be adopted by small scale farmers. The technology should, therefore, be simple, low cost and have little risk to humans and the environment. Tissue culture offers such kind of technology. This communication discusses the status of tissue culture research In Rwanda and how modern biotechnology has led to increased productivity and food security in some developing countries.

Bamboo is one of the fastest growing and highest yielding renewable natural resources with multiple uses in the world. It is used to make furniture, charcoal, food, control soil erosion and can assist in carbon sequestration. The increasing rate of tropical deforestation calls for search for alternative natural resources and the characteristics of bamboo make it a perfect choice. The major constraint in the use of bamboo is the lack of an efficient propagation method. The objective of this study wase to establish an efficient propagation method and to evaluate the adaptability of different bamboo varieties, to Nyungwe National Park (NNP) and the surrounding zones.The trial was conducted in Nyaruguru District, Ruheru Sector bordering Nyungwe National. Basal, middle and apical cuttings were harvested from three bamboo species (Bambusa vulgaris, Arundinaria alpina and an unknown native bamboo growing naturally in the Nyungwe forests). Results of the trial indicated that the three species were not significantly different in terms of stem diameter. However, the number of sprouts that emerged from cuttings differed with species: Bambusa vulgaris producing 22.2 sprouts, Arundinaria alpina 18.1 and the native bamboo producing 15.0 sprouts. On the other hand, the native bamboo had a mean height of 54.0 cm, while Bambusa vulgaris 36.6 and Arundinaria alpina had 30.8 cm..The soaking treatments did not have significant difference on all the parameters evaluated. This reproducible protocol opens new prospects for propagation of bamboo and will go a long way in alleviating the shortage of planting materials and exploiting the enormous potential of bamboo in Rwanda.