Growth And Yield of Sorghum (Sorghum bicolor (L.) Moench) Varities in Sokoto Sudan Savanna of Nigeria

Field trial was carried out during the 2019 rainy season (June to October) at the Dryland Teaching and Research Farm of the Faculty of Agriculture, Usmanu Danfodiyo University, Sokoto to determine the growth and yield of sorghum varieties in the study area. The treatments consisted of five (5) sorghum varieties (Samsorg 45, Samsorg 46, Janjari, Yartawa and Jardawa), the treatments were laid out in a Randomized Complete Block Design (RCBD) replicated three (3) times. Data were collected on the growth and yield of the crop. Janjari and Jardawa varieties were higher in plant height. Jardawa and Yartawa varieties were higher in number of leaves. Janjari and Yartawa varieties were higher in total dry weight. Janjari, Jardawa and Yartawa varieties were higher in harvest index. Yartawa variety was higher in leaf area, leaf area index and 1000-grain weight. Jardawa variety was higher in panicle length. Janjari variety was early in number of days to heading, flowering, and maturity and was higher in dry stalk weight. The grain yield (249 – 1506kg ha-1 ) was higher in Janjari and Yartawa varieties (1268 – 1506 kg ha-1). Based on the findings of this research, it could be concluded that Janjari and Yartawa varieties performed better than other varieties in the study area.

Ripening Response of Sugarcane Varieties to Chemical Ripeners and Economic Benefits during the Early Period of Harvesting at Wonji-Shoa and Metahara Sugarcane Plantations, Central Rift Valley of Ethiopia

Wonji-Shoa and Metahara sugarcane plantations experience reduced sucrose content (%) during the starting period of sugarcane crushing due to the combined influence of high (>27°C) temperature and the presence of high residual soil moisture. Studies elsewhere showed the potential of chemical ripeners in boosting the sucrose content (%), where natural ripening is deterred by these challenges. Accordingly, a field experiment was conducted to evaluate the responsiveness of selected sugarcane varieties to chemical ripeners at both plantations. The treatments consisted of a factorial combination of four sugarcane varieties (B52298, NCo334, C86-56, and SP70-1284) and six ripener treatments: (1) Ethephon™(720 g ai ha−1), (2) Fusilade Forte™(25.6 g ai ha−1), (3) Moddus™ (250 g ai ha−1), (4) Ethephon™ (720 g ai ha−1) + Fusilade Forte™ (25.6 g ai ha−1), (5) Moddus™ (250 g ai ha−1) + Fusilade Forte™ (25.6 g ai ha−1), and (6) Unsprayed (control). The experiment was laid out in a randomised complete block design in a factorial arrangement with three replications. The results showed a significant ( p = 0.025 ) and highly significant ( p = 0.001 ) variety by ripener interaction in stalk height and sucrose content, respectively, while the main effect ripener highly significantly affected stalk weight ( p = 0.001 ) and sucrose yield ( p = 0.003 ). The variety C86-56 sprayed with combinations of Ethephon™ + Fusilade Forte™ and Moddus™ + Fusilade Forte™ had the shortest stalk heights of 1.27 and 1.29 m, respectively, compared with the control. Ethephon™ + Fusilade Forte™ combination resulted in the highest reduction of stalk weight (8.36%), while the lowest was recorded in the sole Moddus™ treatment (6.31%). From the ripener treatments, the Moddus™ + Fusilade Forte™ combination and Ethephon™ + Fusilade Forte™ combination improved sucrose yield by 1.42 and 1.34 t ha−1, respectively, compared with the control. However, in economic terms, the Moddus™ + Fusilade Forte™ combination treatment resulted in the highest marginal rate of return of 1244%. Therefore, the Moddus™ + Fusilade Forte™ combination ripener treatment was found to be promising to be evaluated at a commercial scale on immature sugarcane varieties B52-298, NCo334, and SP70-1284.

Field microenvironments regulate crop diel transcript and metabolite rhythms

Most research in plant chronobiology was done in laboratory conditions. However, they usually fail to mimic natural conditions and their nuanced fluctuations, highlighting or obfuscating rhythmicity. High-density crops, such as sugarcane (Saccharum hybrid), generate field microenvironments that have specific light and temperature, as they shade each other. Here, we measured the metabolic and transcriptional rhythms in the leaves of 4-month-old (4 mo.) and 9 mo. sugarcane grown in the field. Most of the assayed rhythms in 9 mo. sugarcane peaked >1 h later than in 4 mo. sugarcane, including rhythms of the circadian clock gene, LATE ELONGATED HYPOCOTYL (LHY), but not TIMING OF CAB EXPRESSION (TOC1). We hypothesized that older sugarcane perceives dawn later than younger sugarcane, due to self-shading. As a test, we measured LHY rhythms in plants on the east and the west side of a field. We also tested if a wooden wall built between lines of sugarcane also changed their rhythms. In both experiments, the LHY peak was delayed in the plants shaded at dawn. We conclude that plants in the same field may have different phases due to field microenvironments, which may impact important agronomical traits, such as flowering time, stalk weight and number.

Somaclonal Variation in Chrysanthemum × morifolium Protoplast Regenerants

Chrysanthemum × morifolium protoplasts were isolated and regenerated to assess possible protoclonal variation in the regenerants. After a preliminary screening of the potential of different regeneration systems for protoplast regeneration, we produced a series of cut chrysanthemum ‘Arjuna’ leaf protoplast regenerants through liquid culture. Regenerants (54) were vegetatively propagated and grown under a commercial production system in 2 different seasons. All screened regenerants were significantly affected with regard to either flower number, flower size, flower weight, leaf weight, stalk weight, or plant size. A significant plant size reduction in 43/52 and 48/49 regenerants for both seasons was the most recorded effect. Also a reduction in flowering induction time up to 10 days, altered flower types and colors were observed. Differences between growing seasons were notable. Possible molecular backgrounds including genome size variation and commercial applications in breeding of chrysanthemum are discussed.

Integrated selection criteria in sugarcane breeding programs using discriminant function analysis

Background Selection indices help the plant breeders to discriminate desirable genotypes on the basis of phenotypic performance. Therefore, the present study was conducted to evaluate thirty sugarcane genotypes (clones) along with two check cultivars in two cropping seasons at Mattana Agricultural Research Station. Results The results showed the studied traits observed in all genotypes were significantly different. The results could significantly discriminate between low and high sugar yield genotypes by describing eleven traits including sugar yield (ton/fed), cane yield (ton/fed), number of stalk/m2, stalk weight (kg), stalk height (cm), stalk diameter (cm), number of internodes, Brix %, sucrose %, purity %, and sugar recovery %. High sugar yield genotypes were selected by discriminant analysis. The discriminant score (DS) could explain 79.2% of sugar yield variations and had a significant canonical correlation (0.89**). Results of discriminant function analysis (DFA) indicated that the most important traits, in order of appearance, are stalk weight, stalk height, purity %, Brix%, and cane yields. Conclusions Genotypes, G.2017-43, G.2017-42, G.2017-29, G.2017-33, and G.2017-44, showed the highest values of the discriminant score and were recognized as the highest yielder sugarcane genotypes. While the genotypes named Vis, G.2017-30, G.2017-10, G.2017-27, G.2017-25, G.2017-70, G.2017-41, G.2017-40, G.2017-35, and G.2017-58, recognized as the lowest yielder sugarcane genotypes which represent the lowest values of the discriminant score.

Inheritance and Identification of a Major Quantitative Trait Locus (QTL) that Confers Resistance to Meloidogyne incognita and a Novel QTL for Plant Height in Sweet Sorghum

Southern root-knot nematodes (Meloidogyne incognita) are a pest on many economically important row crop and vegetable species and management relies on chemicals, plant resistance, and cultural practices such as crop rotation. Little is known about the inheritance of resistance to M. incognita or the genomic regions associated with resistance in sorghum (Sorghum bicolor). In this study, an F2 population (n = 130) was developed between the resistant sweet sorghum cultivar ‘Honey Drip’ and the susceptible sweet cultivar ‘Collier’. Each F2 plant was phenotyped for stalk weight, height, juice Brix, root weight, total eggs, and eggs per gram of root. Strong correlations were observed between eggs per gram of root and total eggs, height and stalk weight, and between two measurements of Brix. Genotyping-by-sequencing was used to generate single nucleotide polymorphism markers. The G-Model, single marker analysis, interval mapping, and composite interval mapping were used to identify a major quantitative trait locus (QTL) on chromosome 3 for total eggs and eggs per gram of root. Furthermore, a new QTL for plant height was also discovered on chromosome 3. Simple sequence repeat markers were developed in the total eggs and eggs per gram of root QTL region and the markers flanking the resistance gene are 4.7 and 2.4 cM away. These markers can be utilized to move the southern root-knot nematode resistance gene from Honey Drip to any sorghum line.

The Effect of Wheat, Barley, and Oat Root System Interactions, in Two-Species Mixtures

Pot experiments performed in the Institute of Plant Protection - National Research Institute were designed to determine the influence of the root systems of various spring cereal species sown in mixtures. The experiment used the Bryza variety of spring wheat, Antek variety of spring barley, and Cwał variety of oat, sown in two-species mixtures (8 + 8 plants per pot). In three of the six study objects, plastic sleeves were used at the time of sowing the seeds so as to separate the root systems of the cereal species under study. Cereals were harvested at full maturity. The height and number of stalks, the number of cereal spikes (panicles), dry root weight, dry stalk weight, the number of grains per spike (panicle), the 1,000-grain weight, and grain yield were established. The results have shown that the strongest competitor in the mixtures was barley. Barley also responded positively to the presence of both wheat and oat in the mixtures.

Inbreeding in sugarcane varieties

Sugarcane species are allogamous, i.e. selfing is expected to reduce plant vigor. This study was undertaken to obtain and evaluate first-generation inbred lines that may be used for further crosses and determine the extent of inbreeding depression in sugarcane. In this research, 26 parental varieties were self-pollinated to obtain about 19,000 seedlings. Results showed that it is possible to segregate different traits in a given variety and find lines with promising outcome for all assessed characteristics. The soluble solids segregation observed in low and even high-Brix varieties increases the possibility of quick improvement in this trait. Self-pollination did not produce a general loss in yield traits such as soluble solids, stalk number and stalk diameter in any of the 26 varieties, but both stalk height and stalk weight showed strong inbreeding depression. Selfing-derived clones can be used to produce hybrid vigor in crossings.

Growth and yield responses to amendments to the sugarcane monoculture: effects of crop, pasture and bare fallow breaks and soil fumigation on plant and ratoon crops

Yield decline has been a major issue limiting productivity improvement in the Australian sugar industry since the early 1970s and is suspected to be largely due to growing sugarcane in a long-term monoculture. In order to address this issue, rotation experiments were established in several sugarcane-growing regions in Queensland, Australia, to ascertain whether breaking the sugarcane monoculture could, at least in part, assist in overcoming yield decline. The rotation experiments involved other crop species, pasture and bare fallow for different periods of time. When cane was replanted, the growth and yield following breaks was compared with that in a sugarcane monoculture system where the soil was unamended or fumigated before replanting. Yield increases were recorded in the plant and first ratoon (R1) crops in all experiments: in response to soil fumigation (average of 42 and 18%, respectively), and breaks (average of 27 and 30%, respectively). The data indicated that the response to breaks, while smaller in the plant crop, may have greater longevity than the response to fumigation. Further, there were indications that the response to breaks could continue into later ratoons (R2 and R3). Break type had little overall effect with the average response in the plant and R1 crops being 35% for breaks in excess of 30 months. Breaks of longer duration produced larger yield responses: 17% (<12 months), 24% (18–30 months) and 28% (>30 months) in the plant crop. However, the average yield increase over a plant and three ratoon crops when one cane crop was missed (6–12 months’ break) and a grain legume or maize break included was ~20%. Yield increases with breaks and fumigation were due to either increased stalk number, increased individual stalk weight or a combination of both. The component accounting for the majority of the variance changed between experiments, with a general trend for individual stalk weight to have more impact under better late season growing conditions and/or conditions that hampered early stalk development, while stalk number was more important under conditions of late season water stress and/or low radiation input. The results demonstrate that the long-term sugarcane monoculture is having an adverse effect on productivity. Further, breaking the sugarcane monoculture and sacrificing one sugarcane crop is likely to have minimal impact on the supply of cane to the mill. The increase in yield during other stages of the cane cycle is likely to compensate for the loss of 1 year of sugarcane, especially as the crop that is sacrificed is the last and almost always lowest-yielding ratoon.

Effect of Brown Rust on Yield of Sugarcane in Louisiana

Brown rust, caused by Puccinia melanocephala, can cause severe epidemics in susceptible sugarcane cultivars during spring and early summer in Louisiana. The effect of the disease on yield was evaluated in field experiments conducted during three growing seasons. A mixture of three fungicides—azoxystrobin, propiconazole, and tebuconazole—applied biweekly during the spring epidemic period kept brown rust severity low (<5%), and plants protected by fungicide applications throughout the epidemic provided an estimate of attainable yield for comparison with plants naturally infected with rust. A combined analysis over three seasons estimated brown rust caused reductions of 16 and 14% in cane tonnage and total amount of sucrose produced, respectively, in cv. LCP 85-384. The greatest reduction in total sucrose yield of 22% resulted from the epidemic of longest duration, and stalk weight was negatively correlated with rust severity. Comparisons of the yields obtained from plots in which brown rust was controlled early versus late in the epidemic suggested that the impact of the disease is greatest from the middle to late epidemic period when stem elongation has begun.