The topics covered include: cytotaxonomy of the genus Manihot; flower behaviour, hybridization techniques and seed management; breeding strategy (for Africa; for Latin Americas; for Asia); breeding for high yield; breeding for root quality (starch and dry matter content); breeding for low content of cyanogenic glucosides; breeding for high content of protein and other nutritional elements in the root; breeding for resistance to cassava mosaic disease and to cassava brown streak disease; breeding for resistance to cassava bacterial blight (Xanthomonas campestris pv. manihotis [Xanthomonas axonopodis pv. manihotis]); breeding for resistance to fungal diseases; breeding for resistance to mites, mealybugs and whiteflies; breeding for efficient use of basic resources; and cassava breeding in the future, i.e. the role of biotechnology.

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Summary Comparisons of pyrene set were made between raspberry flowers pollinated with undiluted pollen and others pollinated with pollen diluted with talc, or killed pollen. Pollen dilution reduced set but the reduction was not the same for all maternal parents. It also reduced the rate of fruit ripening, increased the proportion of pyrenes without seed content and reduced the tendency for abortive carpels to develop into small empty pyrenes. Observations of numbers of pollen grains germinating in the styles revealed differences attributable to the maternal parents, the pollen germinating poorest on the parent whose pyrene set was reduced most by pollen dilution. There were also maternal × paternal interaction effects on pollen germination. It is concluded that pollen germination was conditioned by growth substances provided partly by the grains themselves and partly by the styles of the seed parent, and that there were interactions between the two sources. Reduction in pollen concentration affected several aspects of early fruit development, but quantitative differences in the amount of pollen applied did not reduce the adverse effects of using diploid pollen. This suggests that such effects do not arise through direct action of the pollen on the maternal tissues.

summary The pigments of Rubus fruits vary in concentration and in the nature of the aglycones and sugars contained in the anthocyanin molecule. Variation in concentration is determined by the genes T, P, Y, Ys, Ycor and possibly Bl and by minor genes. Up to six sugars may be present: one monoglycoside, three diglycosides and two triglycosides. The monoglycoside was present in all the material studied and the presence or absence of the diglycosides rutinose, sophorose, and sambubiose was determined by segregation of the genes R, So and Xy. Synthesis of triglycosides occurred when genes So and R or Xy and R were present together. Cyanidin is the predominant aglycone of raspberries and blackberries, but pelargonidin occurred as traces in raspberries and as the predominant aglycone in R. parviflorus, a species of the sub‐genus Anoplobatus, and in R. pileatus, a species of the sub‐genus Idaeobatus. Knowledge of agenotype's anthocyanin sugars frequently provides evidence of its probable ancestry, but little evidence is available to suggest that any one sugar should be preferred to another.

SUMMARYThe agent of raspberry yellows disease is transmitted by grafting but not by aphids and is resistant to thermotherapy. Further studies showed that it is transmitted by inoculation of sap through seed; it is probably transmitted to plants by pollination. Raspberry bushy dwarf virus (RBDV) shares all these attributes and is known to infect all yellows‐sensitive raspberry cultivars except Puyallup and Sumner; however, neither of these cultivars has been tested by graft inoculation with RBDV. RBDV commonly infects plants symptomiessly, even those of yellows‐sensitive cultivars, but it induced yellows when inoculated either manually to Norfolk Giant raspberry or by grafting to a yellows‐sensitive raspberry selection. The evidence suggests that RBDV is the causal agent of yellows disease but that symptom expression is greatiy dependent on genetic and environmental factors. Many red raspberry cultivars are resistant, probably immune, to the type culture of RBDV and this character was shown to be conferred by a single dominant gene designated Bu.

Food insecurity is a significant public health problem for Indigenous peoples in Canada. A comprehensive literature review is needed to organize the evidence according to the four pillars of food security (i.e., availability, access, utilization, and stability) and identify gaps in the published literature on this topic. Therefore, this scoping review aims to summarize the published research discussing any of the four pillars of food security among Indigenous peoples in Canada. A literature search of the databases: Ovid Medline, EMBASE, Web of Science (Web of Knowledge), and CINAHL as well as Indigenous Studies Portal (up to June 19, 2021) was conducted. Population-based studies of any design were included, except for review-style articles. Articles published in other languages besides English were also excluded. Of the 4687 studies identified by the database searches, 91 met our inclusion criteria. Evidence indicates that all dimensions of food security among Indigenous peoples in Canada have been impacted. Lack of availability of both traditional and market foods is highlighted among Inuit and First Nations communities. Economic disadvantages, high food prices, and lack of access to transportation are major factors affecting the accessibility pillar of food security. Major factors affecting the utilization pillar of food security are the loss of traditional knowledge and skills, lack of knowledge on market foods, low quality of market foods, and food safety issues. Climate change has affected all four pillars of food security among Indigenous peoples. These findings suggest that resolving food insecurity issues among Indigenous peoples in Canada, especially those living in remote communities, requires a culturally specific integrated approach targeting food availability, food cost, food knowledge, food safety, and food quality.

SUMMARY Black raspberry necrosis virus (BRNV) induces a severe apical necrosis in black raspberry (Rubus occidentalis) but fails to induce diagnostic symptoms in red raspberry. However, BRNV infection of F1, F2 and F3 hybrids from the cross black raspberry × red raspberry induced mosaic symptoms of varying intensity but no typical apical necrosis. In a survey of 28 red raspberry cultivars, a few developed severe angular chlorotic leaf spots when infected with raspberry leaf mottle virus and a few others did so when infected with raspberry leaf spot virus. These reactions were determined by single dominant genes designated Lm and Ls respectively. The value of the different host reactions for controlling the effects and spread of these viruses is discussed.