Highlights • Drought stress across all stress levels resulted in a reduction in dry matter production, leaf area index, number of seeds per plant, number of pods per plant, seed size and finally grain yield. • The highest WUE was found in the treatment which was irrigated on fortnightly bases from 36 DAP. The results suggest that drought stress towards the end of the growing season may not cause serious harm in grain yield. • The results suggest that drought stress can be practiced in dry bean production in areas where there is a challenge of irrigation water with consideration of the growth stage of the crop. • The results of the study indicate that drought stress effects on photosynthetic rate were highly significant. • Chlorophyll fluorescence was also affected by drought stress.

Canola (Brassica napus L.) is seen as a dryland crop in many parts of the world. In South Africa, there is growing interest in producing canola under irrigation because of its profitability and beneficial disease control characteristics in a rotation system. The objectives of this study were to identify the growth stage most sensitive to water stress and to determine the effect of water stress on crop growth, phenology, seed and oil yield, water use, and seed oil content. A well watered control was compared with treatments stressed during one of the following stages: vegetative, flowering, or seed filling in replicated field studies during 2002 and 2003 at Pretoria, South Africa. Water stress imposed during flowering delayed maturity by 114 growing degree days. In contrast, water stress imposed during seed fill resulted in 127 growing degree days earlier maturity. The well watered control gave the highest value for leaf area index of 8, water use of 709 mm, seed yield of 3831 kg ha−1, and seed oil content of 398 g kg−1 Canola stressed at flowering gave the lowest values for seed yield of 1361 kg ha−1, seed oil content of 340 g kg−1, and water use of 332 mm. Dry matter production per unit water use at seed filling was only a third of its value during the vegetative and flowering stages. Canola seed and oil yield are most sensitive to water stress at flowering and less sensitive during the vegetative and seed‐filling stages.

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Explorations of the impact of climate change on potential potato yields were obtained by downscaling the projections of six different coupled climate models to high spatial resolution over southern Africa. The simulations of daily maximum and minimum temperatures, precipitation, wind speed, and solar radiation were used as input to run the crop growth model LINTUL-Potato. Pixels representative for potato growing areas were selected for four globally occurring agro-ecosystems: rainy and dry winter and summer crops. The simulated inter-annual variability is much greater for rainfall than for temperature. Reference evapotranspiration and radiation are projected to hardly decline over the 90-year period, whilst temperatures are projected to rise significantly by about 1.9°C. From literature, it was found that radiation use efficiency of potato increased with elevated CO 2 concentrations by almost 0.002 gMJ −1 ppm −1 . This ratio was used to calculate the CO 2 effect on yields between 1960 and 2050, when CO 2 concentration increases from 315 to 550 ppm. Within this range, evapotranspiration by the potato crop was reduced by about 13% according to literature. Simulated yield increase was strongest in the Mediterraneantype winter crop (+37%) and least under Mediterranean summer (+12%) and relatively warm winter conditions (+14%) closer to the equator. Water use efficiency also increased most in the cool rainy Mediterranean winter (+45%) and least so in the winter crop closer to the equator (+14%). It is concluded from the simulations that for all four agro-ecosystems possible negative effects of rising temperatures and reduced availability of water for potato are more than compensated for by the positive effect of increased CO 2 levels on water use efficiency and crop productivity.

Orientation: The unconscious impact of organisational transformation is often neglected and even denied. This research revealed the manifestation and impact of high levels and different forms of anxiety experienced by employees during transformation.Research objective: The objective was to study and describe the manifesting systems psychodynamic behaviour amongst support staff during organisational transformation.Motivation for the study: Organisational transformation is mostly researched from a leadership viewpoint. Little research data are available on the experiences of support staff on the receiving end of decisions about and implementation of transformation.Research design, approach and method: A qualitative approach within the phenomenological hermeneutic interpretive stance was used. The research was set in a government organisation. A semi-structured interview with four conveniently and purposefully chosen support staff members was thematically analysed using systems psychodynamics as theoretical paradigm.Main findings: Four themes manifested, namely de-authorisation and detachment, being bullied and seduced by leadership, the organisation in the mind as incompetent, and a dangerous and persecutory system. In the discussion, the basic assumptions and relevant constructs are interpreted.Practical implications: Understanding the transformation experiences of support staff could assist the industrial psychologist to facilitate appropriate support in coaching more junior staff towards increasing wellness and work performance.Contribution: Organisational transformation is highlighted as an anxiety provoking experience especially on the lower levels of the organisation. Its potentially deep and complex psychological impact could possibly derail parts of the system if not managed in a psychologically contained manner.