To evaluate the effects of defoliation on green forage performance and grain yield (GY) variation in barley, five barley genotypes were imposed on three levels of defoliation treatments over two consecutive growing seasons in this study. The results indicated that green forage yields were significantly improved by repeated defoliation. The traits of green forage quality, including the ratio of dry weight to fresh weight, crude ash and calcium content were improved, while crude protein and crude fat were reduced, and crude fiber and phosphorus contents appeared not to be influenced by repeated defoliation. Plant height (PH), GY and other yield components, grain number per spike and thousand kernel weight, were significantly reduced by defoliation over the two growing seasons, while internode length below spike was less affected. Reduction in spike length and the number of spikes per plant were identified in only one year. Correlation analysis revealed that only PH exhibited a positive correlation with GY. Effects of genotype, interaction between genotype and defoliation, and environments on changes of forage yield and quality and GY were also discussed. Our current work provides a feasible approach to select elite barley cultivars with optimal defoliation treatments for both forage and grain uses in barley breeding programme.

Low-cost methods for enhancement of seed longevity may facilitate biodiversity conservation especially in resource constrained situations. Longevity of 13 cucurbitaceous seed lots belonging to 12 species with mean moisture contents 9.3±0.7% was studied in hermetic storage (HS) and in a liquid consisting of 20% (w/w) CaCl2 in glycerol, following seed to preservative ratio of 1:1 (v/v), at ambient temperature for 24 years. The liquid preservative (LP) was not absorbed by the seeds over the storage period and was harmless to them, drying seeds to about 5% of moisture and maintaining them at this state throughout the storage period. The seeds lost viability in HS in 3.8±0.4 years, while in LP viability was lost in 14–16 years in eight species and the seeds were still viable in five species after 24 years. LP-preserved seeds and also fresh seeds of three species were planted under field conditions. The results validated the use of LP in seed storage for 24 years. The liquid preservation extended longevity of the cucurbit seeds at ambient temperature by drying them and probably maintaining them in oxygen-free environment.

The development of high-yielding, short-duration super-rice hybrids is important for ensuring food security in China where multiple cropping is widely practiced and large-scale farming has gradually emerged. In this study, field experiments were conducted over 3 years to identify the yield formation characteristics in the shorter-duration (∼120 days) super-rice hybrid ‘Guiliangyou 2’ (G2) by comparing it with the longer-duration (∼130 days) super-rice hybrid ‘Y-liangyou 1’ (Y1). The results showed that G2 had a shorter pre-heading growth duration and consequently a shorter total growth duration compared to Y1. Compared to Y1, G2 had lower total biomass production that resulted from lower daily solar radiation, apparent radiation use efficiency (RUE), crop growth rate (CGR), and biomass production during the pre-heading period, but the grain yield was not significantly lower than that of Y1 because it was compensated for by the higher harvest index that resulted from slower leaf senescence (i.e., slower decline in leaf area index during the post-heading period) and higher RUE, CGR, and biomass production during the post-heading period. Our findings suggest that it is feasible to reduce the dependence of yield formation on growth duration to a certain extent in rice by increasing the use efficiency of solar radiation through crop improvement and also highlight the need for a greater fundamental understanding of the physiological processes involved in the higher use efficiency of solar radiation in super-rice hybrids.

In order to identify the effect of burrowing nematodes on the shoots (pseudostem and leaves) of banana plants and to determine whether or not shoot characteristics are associated with plant resistance to nematodes two experiments were conducted in controlled conditions within polytunnels. The banana plants were harvested on three occasions for the measurement of root morphology and biomass. Varieties differed in their resistance to nematodes from resistant (Yg Km5, FHIA 17, FHIA 03) and partly resistant (FHIA 01, FHIA 25) to not resistant (FHIA 23, Williams). Nematodes reduced total plant dry weight at the first harvest in Experiment 1 and by an average of 8.8% in Experiment 2, but did not affect leaf area in either experiment. The ratio of above-ground weight to total plant weight was reduced from 75% to 72% in nematode-infected plants compared with the control plants for all varieties tested in Experiment 1, but was only reduced in FHIA 25 and FHIA 23 in Experiment 2. Varieties differed in above-ground growth. The FHIA varieties had greater shoot weights and leaf area than YgKm5 and Williams. Overall, resistance to nematodes was associated with the partitioning of a greater proportion of biomass to the roots than to above-ground parts

Potatoes are an important cash crop for small-scale producers worldwide. The move away from subsistence to commercialized farming, combined with the rapid growth in demand for processed agricultural products in developing countries, implies that small-scale farmers and researchers alike must begin to respond to these market changes and consider post-harvest treatment as a critical aspect of the potato farming system. This paper presents and assesses a low cost potato-grading machine that was designed explicitly to enable small-scale potato growers to sort tubers by size for supply to commercial processors. The results of ten experiments reveal that the machine achieves an accuracy of sort similar to commercially available graders. The machine, which uses parallel conical rollers, has the capacity to grade different tuber shapes and to adjust sorting classes, making it suitable for locations with high potato diversity. Its relatively low cost suggests that an improved and adapted version of this machine might enhance market integration of small-scale potato producers not only in Peru, but in other developing countries as well.