Aims: Study designed to characterize water economy and biomass production of sugarcane and energy cane genotypes grown in a rain-shelter under well-watered and water-stressed conditions during plant cane and two consecutive ratoon cane phases.
Study Design: Randomized complete block with 5 replications.
Place and Duration of Study: Texas A&M AgriLife Research and Extension Center near Corpus Christi during 2015 and early 2016.
Methodology: Stem cuts of sugarcane line TCP94-5753 and energy cane lines TUS56 and TUS59 were hand-planted in pots. There were three phases including a water-stressed initial plant cane phase and two sequential well-watered ratoon cane phases. Daily whole-plant transpiration was calculated from hourly pot weight changes measured by electronic loadcells. At the end of each phase, plants were harvested to determine above-ground biomass, partitioned into dry leaf blades biomass and stem dry biomass.
Results: No differences in above-ground dry biomass production or water economy among genotypes after the water-stressed plant cane or the first ratoon cane phase, but TUS56 and TUS59 produced 2.32 and 1.83 times more tillers than the sugarcane genotype, respectively. Cumulative transpiration of TUS56 at the end of this first ratoon cane phase was 17% higher than that of TUS59 and TCP94-5753. At the end of the second ratoon cane phase, total above-ground dry biomass were 60% higher in TUS56 than in the sugarcane genotype, but not different from those in TUS59. Cumulative whole-plant transpiration during this phase was about 88% higher for the energy cane genotypes.
Conclusion: Genotypes performed equally in above-ground biomass production and water economy after exposure to water deficits during the initial plant cane phase. No differences in biomass production were observed after the well-watered first ratoon cane phase among genotypes, but TUS56 exhibited more leafiness and transpired more than TUS59 and the sugarcane genotype, and both energy cane lines produced more tillers than the sugarcane.
A field study was conducted at Ofa district-Geleko irrigation site during the off-season of 2016/17 cropping season with the objective of evaluating different varieties and row spacing on growth, yield and yield components of maize. Four plant row spacing (45 cm, 55 cm, 65 cm and 75 cm) and three maize varieties (‘BH-540’, Lemu‘P3812W’and Jabi ‘PHB 3253’) were tested in factorial arrangement laid out in RCBD replicated three times. Data on yield and yield components of the crop were recorded. The result indicated that most of the parameters such as number of ears per plant, ear diameter, 1000 kernel weight, number of kernels per ear, number of kernels per rows, grain yield per hectar were significantly influenced by the interaction effect of row spacing and varieties. Significantly highest grain yield were produced by maize variety Lemu grown at row spacing of 65 cm, which is statistically similar with variety BH-540 grown at row spacing of 65 and 75 cm and also the same variety grown at row spacing of 75 cm, while lowest was recorded for variety Jabi grown at row spacing of 45 cm. Based on these results, it can be concluded that under irrigated condition Lemu and BH-540 maize varieties at 65-75 cm row spacing resulted higher biomass and grain yield of maize and may be used by farmers of the area. However, since the study was at only one location and for single cropping season repeating the experiment across different locations and years is needed to reach at conclusive recommendations.
Field study was undertaken to determine the population of three major pod sucking bugs namely Riptortus dentipes Fab. (Hemiptera: coreidae), Clavigralla tomentosicollis Stall (Hemiptera: coreidae), Anoplocnemis curvipes Fab (Hemiptera: coreidae) and their effect on damage, yield (kg ha-1) and yield components under varying plant densities and planting dates. The experiment was carried out at the Postgraduate Teaching and Research Farm, Department of Crop Science and Technology, Federal University of Technology, Owerri Imo State. Experiment was laid out in a 3 x 4 factorial and treatments comprised of four plant density of 190,474 plants ha-1, 125,000 plants ha-1, 80,000 plants ha-1, 55,556 plants ha-1 and three planting dates, April (early season), July (Mid-season), and October (late season), 2009 and 2010. The results, show that there was significant (p<0.05) population of the pod sucking bugs on pigeonpea flowers and pods at high plant density and low on plants at low plant density. There was significant (p<0.05) population of C. tomentosicollis and A. curvipes in October while April and July planting seasons showed absence of C. tomentosicollis and A. curvipes The population of R. dentipes occurred throughout the season with peak population in April which decreased as planting was delayed till October. Also plants at high density recorded high pod and seed damage resulting in low values of seed yield (147.90 kg ha-1) in 2009, (168.80 kg ha-1) in 2010 when compared with pigeonpea planted at low density which had low pod and seed damage with high seed yield of 223.33 kg ha-1 in 2009, and 268.83 kg ha-1 in 2010. Also yield components like 100 pod/seed weight (g), pod/seed yield (g) per plant, number of seeds per pod were low on plants at high density, but high on plants at low density. July planting season recorded the lowest pest loads, pods/seed damage, with resultant high pod/seed yield and yield components compared with April and October planting seasons. Therefore, for high seed yield with minimal damage by pod sucking bugs, planting the early maturing pigeonpea in July at low density should be incorporated into farming systems in this zone as integrated Pest Management alternative.
This study aimed to evaluate the effect of different budbreak promoters on low chilling apple trees, Eva and Castel Gala, in mild winter conditions of Southern Brazil. An experimental design was randomised blocks, with four replications, and the experimental unit was composed of two plants, on 4x2 factorial arrangement (four treatments and two cultivars). This research was carried out during growing season 2014/2015, in an experimental apple orchard located at Palma Agriculture Center, Federal University of Pelotas, Southern Brazil. Four treatments were applied: Erger 3% + calcium nitrate 3%; Erger 5% + calcium nitrate 5%; hydrogen cyanamide 1.5% + mineral oil 3% and control. It was recorded phenological stages: beginning, full and the end of blooming; budbreak of axillary buds and fruit set. The productive parameters were analysed: average fruit weight (g), yield efficiency (kg-cm-2) and yield (Mg ha-1). All treatments reduced blooming period and improved the synchronisation in both cultivars. There was an increase in budbreak of axillary buds, whereas, in ‘Eva' apple trees, the treatments with Erger had higher budbreak rates than hydrogen cyanamide. In ‘Eva', the application of budbreak promoters reduced fruit set and increased the average fruit weight, yield and yield efficiency, when compared to control trees. However, these results were not observed in ‘Castel Gala'. The combination of Erger and calcium nitrate showed similar and higher performance than the combination of hydrogen cyanamide and mineral oil in the budbreak percentage in ‘Castel Gala' and ‘Eva', respectively.
The knowledge about the interactions between pit dimensions and propagation methods can provide important information for the Conilon coffee crop since these basic steps can influence the entire production cycle of the tillage. The objective of this study was to access the initial development (vegetative and radicular) of Conilon coffee propagated by seed and stake and cultivated in pits with different dimensions. The experiment was a randomized block design with four replicates of three plants. The treatments were arranged in a 2x3 factorial scheme, with two propagation methods (seed and cutting), and three pit dimensions (20x20x20 cm, 30x30x30 cm and 40x40x40 cm). The number of leaves, stem diameter, plant height, main root length, root volume, dry mass of aerial part and root, and relation aerial/root part, were evaluated 18 months after transplanting. There was a significant interaction between the propagation methods and the pit dimensions, only for the number of leaves and root length, wherein the smaller pits, the seedlings propagated by seed were superior to the clonal ones. The other variables analyzed presented significant differences only for the pit dimensions factor. The initial development of the Conilon coffee isn't influenced by the propagation method. The pit dimensions directly affects the initial development of the Conilon coffee Incaper ‘Vitória 8142' clone number 10, and pits with the largest dimensions provide an increase in the initial development of the plants.