Influence of NPK-application to seed-potato crops on the productivity of the progeny
SummaryThe amount of P- and K-application to the seed-potato crop did not show any influence on the chemical composition of the immature harvested tubers, nor on the productivity if used as seed. Nitrogen had a marked influence on the chemical composition of the tubers.Seed from plots with high nitrogen dressing showed a tendency to give fewer main stems. Concerning the productivity of the seed the experiments showed contradictory results. It is concluded that the amount of fertilizer applied to the seed-potato crop is of little importance for the productivity of the progeny.
The effects of seed production practices on the productivity of the succeeding ware potato crop
The project examined the effects of seed potato production on the performance of the seed in the following ware crop. The research was conducted in Tasmania, Australia, where the temperate maritime climate supports a lengthy growing season and a low aphid borne virus pressure permits crops to be grown to senescence, or defoliated if prevention of oversized tubers is desired. Harvest in the relatively cool autumn/winter may be delayed many weeks after skin set as soil temperatures do not fall below -1˚C often. These factors permit a greater range of seed crop management options than is present in most other seed production regions of the world. Significant variability in the performance of seed lots grown in Tasmania has been documented, and could not be accounted for by differences in storage conditions, suggesting that seed crop production conditions may be responsible. Recognition of this possibility by the potato industry in Tasmania was the impetus for this project. 
Seed tubers of cultivar Russet Burbank produced under various nitrogen and phosphorous nutrition, and planting density treatments were found to perform in the following season without significant differences in emergence date stem number or yield. Significant seed production practice effects on seed performance were found where planting date, time of defoliation and time of harvest following defoliation treatments were imposed. The results of the study confirmed that differences in ware crop growth and yield may be at least partially attributed to seed crop management practices. Sufficient evidence was generated to support the conclusion that, under Tasmanian production conditions, planting seed crops early in the season and defoliating prior to full crop maturity along with harvesting shortly after defoliation will increase the likelihood of producing seed tubers with higher productivity in the following season. 
The seed performance responses found following seed crop defoliation date treatments were not consistent, ranging from no differences between defoliated and non-defoliated treatments to ten percent differences in yield. It was concluded that the stage of development or physiological status of the plant at the time of defoliation determines the effect on seed physiological status at harvest. In addition, significant differences in seed performance were noted between seed harvested shortly after defoliation and seed harvested after extended storage in the soil following defoliation. The behaviour of in ground stored seed following the stress associated with defoliation suggested that recovery from stress may be possible during seed development even when stems are removed. This capacity for recovery may explain differences in seed tuber responses between studies examining effects of early defoliation treatments. 
The effect of seed production practices in seed physiological quality was shown to be complex, but with increasing importance placed in ware crop production on attaining consistent high yields of tubers in narrow size ranges, the capacity to manage seed physiological quality is very relevant to the potato industry.
Early Missionaries and the Ethnolinguistic Factor During the ‘Invention of Tribalism’ in Zimbabwe
There is evidence from across the disciplines that at least some of the contemporary regional names of African tribes, dialects and languages are fairly recent inventions in historical terms. This article offers some evidence from Zimbabwe to show that missionary linguistic politics were an important factor in this process. The South African linguist Clement Doke was brought in to resolve conflicts about the orthography of Shona. His Report on the Unification of the Shona Dialects (1931) shows how the language politics of the Christian denominations, which were also the factions within the umbrella organization the Southern Rhodesia Missionary Conference, contributed quite significantly to the creation and promotion of Zezuru, Karanga and Manyika as the main groupings of dialects in the central area which Doke later accommodated in a unified orthography of a unified language that was given the name Shona. While vocabulary from Ndau was to be incorporated, words from the Korekore group in the north were to be discouraged, and Kalanga in the West was allowed to be subsumed under Ndebele. Writing about sixty years later, Ranger focusses more closely on the Manyika and takes his discussion to the 1940s, but he also mentions that the Rhodesian Front government of the 1960s and 1970s deliberately incited tribalism between the Shona and the Ndebele, while at the same time magnifying the differences between the regional divisions of the Shona, which were, in turn, played against one another as constituent clans. It would appear then that, for the indigenous Africans, the price of Christianity, Western education and a new perception of language unity was the creation of regional ethnic identities that were at least potentially antagonistic and open to political manipulation. Through many decades of rather unnecessary intellectual justification, and as a result of the collective colonial experience through the churches, the schools and the workplaces, these imposed identities, and the myths and sentiments that are associated with them, have become fixed in the collective mind of Africa, and the modern nation states of the continent now seem to be stuck with them. Missionaries played a very significant role in creating this scenario because they were mainly responsible for fixing the ethnolinguistic maps of the African colonies during the early phase of European occupation. To a significant degree, these maps have remained intact and have continued to influence African research scholarship.