Months After Planting Research Articles

Water Use Efficiency Characteristics and Their Contributions to Yield in Diverse Sugarcane Genotypes with Varying Drought Resistance Levels Under Different Field Irrigation Conditions

Drought is the major abiotic constraint affecting sugarcane productivity and quality worldwide. This obstacle may be alleviated through sugarcane genotypes demonstrating good water use efficiency (WUE) performance. This study aims to investigate the WUE characteristics of various sugarcane genotypes under different soil water availability levels. Plant and ratoon field experiments were conducted using a split-plot randomized complete block design with three replications. The main plots were assigned three types of irrigation: (1) rainfed conditions (RF), (2) field capacity conditions (FC), and (3) half-available water (½ AW). The subplots consisted of six sugarcane genotypes with varying levels of drought resistance, i.e., KK3, UT13, Kps01-12, KKU99-03, KKU99-02, and UT12. Data on yield, stalk numbers, stalk diameter, height, and WUE were collected throughout the crop cycle for both plant and ratoon crops. For the plant crop, the net photosynthesis rate, transpiration rate, stomatal conductance, and leaf area index (LAI) were recorded during the crop period. In both plant and ratoon crops, the WUE in the RF treatment was lower than in the FC and ½ AW treatments during the drought stress period 4 months after planting (MAP). In the recovery phase, the WUE in the ½ AW treatment fell between the FC and RF treatments. The RF treatment exhibited the lowest WUE compared to the other two water regime treatments at the maturity stage. The drought-resistant genotypes KK3 and UT13 maintained high WUE values throughout both the drought and recovery periods and exhibited outstanding LAIs at 4 and 6 MAP. A significant relationship existed between WUE and LAI during these periods. Moreover, WUE was positively correlated with cane yields and yield components, such as stalk weight, shoot diameter, and height, during recovery and tiller number and height during ripening. Therefore, WUE and LAI are efficient parameters for supporting and maintaining growth and yield during water deficit and recovery phases under rainfed conditions.

Identification of sodicity-tolerant banana varieties to harness the salt-affected ecosystem

"Salt Affected Soils" (SAS) refers to a category of soils that contain either an excess of soluble salts or exchangeable sodium. Soils are divided into four categories: normal, saline, sodic, and saline-sodic, based on the electrical conductivity (EC), pH and exchangeable sodium percentage (ESP) measurements. At the Horticultural College and Research Institute for Women in Trichy, fifteen genotypes of bananas were assessed for growth, yield, and physiological parameters in a saline-sodic environment. Four replications of the field experiment were set up in RBD and evaluated for three years. The growth physiological and biochemical characters were recorded in the seventh month after planting (MAP), and the bunch characters were recorded at harvest time. FHIA 1 (83.4%), Saba (81.0%) and Karpooravalli (78.0%) had the highest relative water content. The highest yield was recorded in FHIA-1 (23.5 kg), Saba (22.2 kg), Udhayam (22.5 kg) and Karpooravalli (22.0 kg). The sodicity injury symptoms in the leaves were evaluated using a scoring technique, and the genotypes FHIA-1(1.0) Saba recorded the lowest score for sodicity damage. A significant negative correlation was observed between salt injury degree and leaf K+/Na+. So, the varieties that maintain higher K+/Na+ ratio in leaf and root are salt tolerant. The general ranking of the banana varieties for salt tolerance was FHIA 1 > Saba > Karpooravalli > Bangrier > Ash Monthan > Veneetu Mannan > Udhayam. A comparative field trial for the 15 banana types showed that Saba, FHIA-1 and Karpooravalli could withstand sodic conditions in the field in terms of bunch characteristics, biochemical parameters, and plant growth. Grand Naine, Rasthali and CO 1 were vulnerable to sodicity stress. Regardless of cultivar, sodicity stress increased the days needed for shooting and harvest.

Physiological Characterization of Banana Germplasm of North East India for Tolerance against Moisture Deficit

Background: Water deficit stress is a serious environmental constrain to banana productivity in north east (NE) India. A field experiment was conducted to appraise the performance of 29 banana germplasm of NE India under moisture deficit condition of Assam that naturally prevails due to deficit rainfall every year during November to January. Methods: Randomized block design with five replications was the experimental design used. Irrigation was not applied during the crop growing season. Various physio-chemical parameters were measured in the main crop on 7th and 9th months after planting (MAP) that coincided with November and January. Result: Significant variations were observed in leaf relative water content, leaf area plant-1, leaf area index, total chlorophyll content, leaf proline content, lipid peroxidation, hands bunch-1 and bunch weight amongst germplasm studied. During moisture deficit period, germplasm Barjahaji, Bhimkal, Athiya and Bogimonahar could maintained better values in the physio-chemical traits studied except lipid peroxidation. The germplasm that showed superior values in the physio-chemical traits and lower value for lipid peroxidation registered the higher bunch weight. Significant positive correlation of bunch weight with leaf area (0.42 and 0.45 respectively for 7th and 9th MAP) and relative leaf water content (0.38 respectively for both 7th and 9th MAP) and significant negative correlation with lipid peroxidation (-0.45 and -0.49 respectively for 7th and 9th MAP) were observed at 5 per cent level of significant. Significant strong positive correlation between leaf chlorophyll content and proline content in leaf (0.85) was observed at 9th MAP. Germplasm Barjahaji, Bhimkal, Bogimanohar and Athiya are considered physiologically more tolerant to moisture deficit which can be used for future breeding programs and the physio-chemical parameters viz., leaf area, chlorophyll content, relative leaf water content and proline content can be considered as physiological indices for drought tolerance.

Effect of Harvesting Time in Growth Performance and Energy Crops Productivity of Napier (<i>Pennisetum purpureum cv</i>. Taiwan) Exposed under CO<sub>2</sub> Elevated Conditions

Napier grass is crucial in reducing greenhouse gas emissions by substituting non-renewable resources. When Napier grass is burned, the carbon dioxide (CO<sub>2</sub>) released is roughly equal to the amount absorbed during its growth, making it a potentially carbon-neutral energy source. This study investigates the impact of ratooning (repeated harvesting) on various aspects of Napier grass, including growth, physiology, biomass production, nutrient content, and chemical analysis. It also explored the interaction between elevated CO>sub>2</sub> levels and ratooning. Two experiments were conducted over 12 months. Experiment 1 took place in an open field at the Faculty of Agriculture, Universiti Putra Malaysia (UPM), with two treatments: no ratooning and ratooning at three months after planting (MAP). Experiment 2 was conducted in an open field at UPM and a greenhouse at Tenaga National Berhad Research, Kajang, Selangor. Eight combination treatments were studied: (T1) 1-month elevated CO<sub>2</sub> (MECO<sub>2</sub>) - no ratooned, (T2) 1 MECO<sub>2</sub>-R at 3 MAP, (T3) 2 MECO<sub>2</sub>-noR, (T4) 2 MECO<sub>2</sub>-R at 3 MAP, (T5) 5 MECO<sub>2</sub>-noR, (T6) 5 MECO<sub>2</sub>-R at 3 MAP, (T7) 12 MECO<sub>2</sub>-noR, and (T8) 12 MECO<sub>2</sub>-R at 3 MAP. The results indicated that, in Experiment 1, no ratooning was more favourable for all parameters compared to ratooning. In Experiment 2, a 1-month exposure to elevated CO<sub>2</sub> showed better results compared to longer exposure periods. In conclusion, Napier grass performed better when not subjected to ratooning and exposed to short-term elevated CO<sub>2</sub> levels. This research highlights the potential of Napier grass as a sustainable and carbon-neutral energy source.

Photosynthetic Performance, Carbohydrate Partitioning, Growth, and Yield among Cassava Genotypes under Full Irrigation and Early Drought Treatment in a Tropical Savanna Climate.

In a tropical savanna climate like Thailand, cassava can be planted all year round and harvested at 8 to 12 months after planting (MAP). However, it is not clear how water limitation during the dry season without rain affects carbon assimilation, partitioning, and yield. In this field investigation, six cassava genotypes were planted in the rainy season (August 2021) under continuous irrigation (control) or subjected to drought for 60 days from 3MAP to 5MAP during the dry season (November 2021 to January 2022) with no irrigation and rainfall. After that, the plants were rewatered and continued growing until harvest at 12MAP. After 60 days of stress, there were significant reductions in the mean net photosynthesis rate (Pn), petiole, and root dry weight (DW), and slight reductions in leaf, stem, and tuber DW. The mean starch concentrations were reduced by 42% and 16% in leaves and tubers, respectively, but increased by 12% in stems. At 6MAP after 30 days of rewatering, Pn fully recovered, and stem starch was remobilized resulting in a dramatic increase in the DW of all the organs. Although the mean tuber DW of the drought plants at 6MAP was significantly lower than that of the control, it was significantly higher at 12MAP. Moreover, the mean tuber starch concentration at 12MAP of the drought plants (18.81%) was also significantly higher than that of the controls (16.46%). In the drought treatment, the high-yielding varieties, RY9, RY72, KU50, and CMR38-125-77 were similarly productive in terms of tuber DW and starch concentration while the breeding line CM523-7 produced the lowest tuber biomass and significantly lower starch content. Therefore, for cassava planted in the rainy season in the tropical savanna climate, the exposure to drought during the early growth stage was more beneficial than the continuous irrigation.

Determination of genomic regions associated with early storage root formation and bulking in cassava.

Early cassava storage root formation and bulking is a medium of escape that farmers and processors tend to adopt in cases of abiotic and biotic stresses like drought, flood, and destruction by domestic animals. In this study, 220 cassava genotypes from the International Institute of Tropical Agriculture (IITA), National Root Crops Research Institute (NRCRI), International Center for Tropical Agriculture (CIAT), local farmers (from farmer's field), and NextGen project were evaluated in three locations (Umudike, Benue, and Ikenne). The trials were laid out using a split plot in a randomized incomplete block design (alpha lattice) with two replications in 2 years. The storage roots for each plant genotype were sampled or harvested at 3, 6, 9, and 12 month after planting (MAP). All data collected were analyzed using the R-statistical package. The result showed moderate to high heritability among the traits, and there were significant differences (p< 0.05) among the performances of the genotypes. The genome-wide association mapping using the BLINK model detected 45 single-nucleotide polymorphism (SNP) markers significantly associated with the four early storage root bulking and formation traits on Chromosomes 1, 2, 3, 4, 5, 6, 8, 9, 10, 13, 14, 17, and 18.A total of 199 putative candidate genes were found to be directly linked to early storage root bulking and formation. The functions of these candidate genes were further characterized to regulate i) phytohormone biosynthesis, ii) cellular growth and development, and iii) biosynthesis of secondary metabolites for accumulation of starch and defense. Genome-wide association study (GWAS) also revealed the presence of four pleiotropic SNPs, which control starch content, dry matter content, dry yield, and bulking and formation index. The information on the GWAS could be used to develop improved cassava cultivars by breeders. Five genotypes (W940006, NR090146, TMS982123, TMS13F1060P0014, and NR010161) were selected as the best early storage root bulking and formation genotypes across the plant age. These selected cultivars should be used as sources of early storage root bulking and formation in future breeding programs.

Identification and expression of gene loci underlying the quantitative trait loci of starch content in cassava

ABSTRACT In this study, a genetic linkage map was developed based on simple sequence repeat (SSR) markers to aid in the identification and expression analysis of gene loci underlying the quantitative trait loci (QTL) of starch content (SC) in cassava (Manihot esculenta). A total of 912 polymorphic loci from 4,515 tested SSRs were mapped into 18 linkage groups. QTL analysis revealed four loci with highly significant associations with starch. Gene annotation was performed, and potential genes related to starch synthesis were identified. Of these, expression of four genes related to starch synthesis (Raffinose synthase [RS], Phosphoenolpyruvate kinase [PK], Glucose-6-phosphate [G6P], and Glycogen synthase kinase 3 [GSK-3]) was investigated by real-time PCR assays. The results found a statistically significant difference (p < 0.05) at 3 months after planting (MAP) in all the tested genes, whereas a higher expression was detected in the low-SC group with specific genotypes of linked markers. A higher level of expression was observed in the RS, PK, and G6P genes at six and nine MAP, indicating that starch accumulation mainly occurs after 3 MAP, during which the root system begins to form. The potential genes identified in this study could provide a better understanding of the starch biosynthesis mechanism, and could be useful for applications in marker-assisted selection to facilitate cassava breeding programs in the future.

Humic acid enriched with urea and NPK factory by-products promoted the growth and yield of Saccharum officinarum L.

Nutrient uptake efficiency in sugarcane (Saccharum officinarum L.) must be increased using organic matter to restore soil fertility, resulting in greater productivity. The humic substance is a complex organic material that is excellent for overcoming this challenge. This study aimed to determine the effect of the humic acid enriched by liquid urea by-product (PSUC) and liquid NPK by-product (PSNC) application on the growth and productivity of sugarcane. The experiment was conducted from October 2021 to September 2022 on PT RNI plantation land, Jatitujuh, Majalengka. The research was arranged in a completely randomized (CRD) using two different humic acid product prototypes (PSUC and PSNC) with two evaluation times, a screening and a semi-pilot scale. Solid humic at a dose of 15 Kg ha⁻¹ was applied by mixing it with inorganic fertilizers, while liquid humic at a total dose of 15 L ha⁻¹ was applied by foliar spray technique at 1, 2, and 3 months after planting (MAP). The results showed that applying humic acid PSUC and PSNC enhanced sugarcane shoot growth, segmented stem number, and diameter. In addition, it could consistently promote sugarcane yields on the semi-pilot scale up to 19.18% and 24.26% under humic acid PSUC and PSNC treatments, respectively. Therefore, both in the screening and semi-pilot evaluation, the solid and liquid humic acid PSUC and PSNC applied simultaneously are potential organic materials to enhance sugarcane growth and yield.

Resistance to Cassava Whitefly (Bemisia tabaci) among Eastern and Southern African Elite Cassava Genotypes.

Cassava whitefly, Bemisia tabaci, directly damages cassava leaves by feeding on phloem, causing chlorosis and abscission, leading to a yield loss of up to 50%. The pest also causes indirect damage through sooty mold formation. Most Ugandan cassava varieties resist cassava mosaic disease (CMD) and tolerate cassava brown streak disease (CBSD), but little is known about their response to whitefly infestation. The main objective of this study was to identify cassava genotypes with putative resistance to whitefly in Uganda. This was conducted on 24 improved cassava varieties in three agro-ecological zones during the second rains of 2016. Monthly data were taken for adult and nymph counts, whitefly and sooty mold damage, and CMD and CBSD severities from 2 to 9 months after planting (MAPs). The results show that the whitefly population is highly significantly (p < 0.000) amongst varieties across the three agro-ecological zones. Mkumba consistently supported the low adult numbers and nymphs. The findings demonstrate the potential of the improved cassava varieties as sources of whitefly resistance for sustainable management.

Effect of crop pattern and types of manure on the growth of Sappan wood (Caesalpinia Sappan L.) in Jatinangor, West Java, Indonesia

Sappan wood plants are one of the medicinal plants in Indonesia. Considering the potential of Sappan wood plants in the health and industrial sectors, special cultivation techniques are required to ensure that Sappan wood plants can grow with a large stem diameter. A large stem diameter can be achieved by using the appropriate planting distance. The right planting distance requires land with sufficient organic content. This research aims to determine the optimum planting distance and the appropriate type of organic material to produce Sappan wood plants with a large diameter. The experimental design used was a Split Plot Design, with planting distance (J) as the main plot and organic fertilizer (P) as the sub-plot. The planting distance factor levels were J1 = 1m x 1m, J2 = 2mx2m cm, J3 = 3m x3m. The organic fertilizer factor levels were P1 = Cow Manure Fertilizer, P2 = Chicken Manure Fertilizer, and P3 = Sheep Manure Fertilizer. The results showed an interaction between the planting distance treatment and the use of manure fertilizer on the parameters of stem diameter and soil pH of Sappan wood plants at 3 MAP (months after planting). The planting distance treatment independently influenced the results, with a 1m x 1m planting distance providing the best results for plant height and stem diameter. In general, the application of different types of manure did not significantly affect the growth of Sappan wood plants.

Application of biostimulant consortium to increase the growth of sugarcane (Var. Cenning) in a dry land

Abstract Sugarcane is considered one of the most promising crops. The growth of the crop is affected by photosynthesis and toter and nutrient absorption by plants. Biostimulant is a non-nutrient biomaterial that is proven to improve crop growth. Based on this idea, Biostimulant technology can be used as an alternative to enhance sugarcane growth. This research aimed to assess the Biostimulant consortium (Sucrosin, humic acid, and AM fungal) to improve the growth of the sugarcane var. Cenning in a dry land. The study tested two treatments, i.e., control (standard procedures) and Biostimulant Consortium application. Sucrosin was applied on 1, 3, 4, and 5 months after planting (MAP) by using a foliar spray. Application of mycorrhizal fungi was spread around the roots area of sugarcane crops. In contrast, the application of humic acid was sprayed on the ground as a coating agent for inorganic fertilizers. Coating fertilizer is carried out by mixing a humic acid solution with as much as 1% of the fertilizer. The research showed the treatment of the Biostimulant Consortium yielded significant results in the sugarcane growth compared to the control on 8 MAP. Biostimulant Consortium can improve crop height and stem diameter significantly up to 30-40% compared to control. It indicates that the Biostimulant consortium’s treatment can improve sugarcane’s vegetative growth in s dry land.

Evaluation of Growth, Chlorophyll Content, and Photosynthesis Rate of Curcuma xanthorrhiza With Different Shade Levels

Curcuma xanthorrhiza RoxB. is a medicinal plant found in Indonesia and is often cultivated for therapeutic purposes. Curcuma xanthorrhiza typically thrives in shaded, low-light environments. In this study, plant growth, photosynthetic rate, and chlorophyll content of C. xanthorrhiza in the same growing environment with different shade treatments were evaluated. The level of shade was adjusted using paranet at 0%, 25%, 50%, and 75%. Growth observations of C. xanthorrhiza were carried out from 1 to 6 months after planting (MAP). Chlorophyll content was measured using a UV-Vis spectrophotometer at 649 and 665 nm. The photosynthetic rate was measured using Li-Cor 6400 at 5 MAP. The results revealed that 50% shade gave the best response for plant height at 2 MAP. However, the highest number of leaves was found at 25% shade at 4 and 5 MAP. The shade level of 25% produced a significant response for C. xanthorrhiza rhizome biomass. The highest photosynthetic rate was found at 0% shade (26.69 µmol CO2 m-2s-1) and the lowest at 75% shade (15.12 µmol CO2 m-2s-1). Meanwhile, the chlorophyll content and number of tillers of C. xanthorrhiza leaves were unaffected by shade treatment. This study shows that shade treatments at 25%-50% levels gave the best growth responses in the C. xanthorrhiza plants.

Cut, Root, and Grow: Simplifying Cassava Propagation to Scale.

Cassava (Manihot esculenta Crantz) is an essential crop with increasing importance for food supply and as raw material for industrial processing. The crop is vegetatively propagated through stem cuttings taken at the end of the growing cycle and its low multiplication rate and the high cost of stem transportation are detrimental to the increasing demand for high-quality cassava planting materials. Rapid multiplication of vegetative propagules of crops comprises tissue culture (TC) and semi-autotroph hydroponics (SAH) that provide cost-effective propagation of plant materials; however, they contrast the need for specific infrastructure, special media and substrates, and trained personnel. Traditional methods such as TC and SAH have shown promise in efficient plant material propagation. Nonetheless, these techniques necessitate specific infrastructure, specialized media and substrates, as well as trained personnel. Moreover, losses during the intermediate nursery and adaptation stages limit the overall effectiveness of these methods. Building upon an earlier report from Embrapa Brazil, which utilized mature buds from cassava for rapid propagation, we present a modified protocol that simplifies the process for wider adoption. Our method involves excising single nodes with attached leaves from immature (green) cassava stems at 2 months after planting (MAP). These nodes are then germinated in pure water, eliminating the need for specific growth substrates and additional treatments. After the initial phase, the rooted sprouts are transferred into soil within 1-8 weeks. The protocol demonstrates a high turnover rate at minimal costs. Due to its simplicity, cost-effectiveness, and robustness, this method holds significant promise as an efficient means of producing cassava planting materials to meet diverse agricultural needs.

Integrated transcriptomics and metabolomics analysis provides insights into aromatic volatiles formation in Cinnamomum cassia bark at different harvesting times.

Cinnamomum cassia Presl, classified in the Lauraceae family, is widely used as a spice, but also in medicine, cosmetics, and food. Aroma is an important factor affecting the medicinal and flavoring properties of C. cassia, and is mainly determined by volatile organic compounds (VOCs); however, little is known about the composition of aromatic VOCs in C. cassia and their potential molecular regulatory mechanisms. Here, integrated transcriptomic and volatile metabolomic analyses were employed to provide insights into the formation regularity of aromatic VOCs in C. cassia bark at five different harvesting times. The bark thickness and volatile oil content were significantly increased along with the development of the bark. A total of 724 differentially accumulated volatiles (DAVs) were identified in the bark samples, most of which were terpenoids. Venn analysis of the top 100 VOCs in each period showed that twenty-eight aromatic VOCs were significantly accumulated in different harvesting times. The most abundant VOC, cinnamaldehyde, peaked at 120 months after planting (MAP) and dominated the aroma qualities. Five terpenoids, α-copaene, β-bourbonene, α-cubebene, α-funebrene, and δ-cadinene, that peaked at 240 MAP could also be important in creating C. cassia's characteristic aroma. A list of 43,412 differentially expressed genes (DEGs) involved in the biosynthetic pathways of aromatic VOCs were identified, including phenylpropanoids, mevalonic acid (MVA) and methylerythritol phosphate (MEP). A gene-metabolite regulatory network for terpenoid and phenylpropanoid metabolism was constructed to show the key candidate structural genes and transcription factors involved in the biosynthesis of terpenoids and phenylpropanoids. The results of our research revealed the composition and changes of aromatic VOCs in C. cassia bark at different harvesting stages, differentiated the characteristic aroma components of cinnamon, and illuminated the molecular mechanism of aroma formation. These foundational results will provide technical guidance for the quality breeding of C. cassia.

Response of cassava (Manihot esculenta Crantz) genotypes to natural infestation by scale insect pest Stictococcus vayssierei Richard (Hemiptera: Stictococcidae)

Cassava is mostly grown for its starchy roots, which ensure food security. However, it is heavily attacked by the African root and tuber scale (ARTS) Stictococcus vayssierei in Central Africa. This pest is a severe constraint to the production of cassava, food and income security for smallholder farmers. Crop resistance development through the selection of varieties with resistant traits against targeted pests is a promising approach to pest control. This study investigated cassava genotypes' response to natural infestation and determined their resistance levels against S. vayssierei. Six cassava genotypes (two local and four improved) were planted in a completely randomized block design with four replicates. Agronomic parameters and ARTS density were evaluated at 3, 6, 9 and 12 months after planting (MAP). Biochemical content was determined on the pith and cortex of 12 MAP aged tuberous roots. As a result, the improved Excel variety recorded the highest scale density per plant with 102.83 ± 4.14 ARTS/P at 9 MAP. At 12 MAP, high activity of total cyanide (69.18 ± 0.88 and 69.16 ± 1.44 mg/kg) and phenylalanine ammonia-lyase (0.142 ± 0.020 and 0.145 ± 0.010 ΔA/min/mg) were observed in the cortex of the tuberous roots of the improved varieties TMS 96/0023 and TMS 92/0057 which were colonized by the lowest ARTS density. The local variety (Douma) had a high content of total phenols (44.87 ± 1.15 µg/g) in the pith. It also produced the highest yield (23.8 ± 2.9 t ha-1). Varieties TMS 96/0023, TMS 92/0057 and Douma may be the most suitable varieties for the control of ARTS stress.

Early tree growth and crop yields under and Prosopis cinerariaAilanthus excelsa based agroforestry system in north western India

A field experiment was initiated in 2017 to evaluate the effect of tree species and tree spacing on intercrop productivity and tree growth with advancing age of and in an agroforestry Prosopis cinerariaAilanthus excelsasystem at Bikaner, Rajasthan. Both and were planted at three spacings: 4m × 4m, 6m × P. cinerariaA. excelsa6m and 8m × 8m; and L. Taub. (Cluster bean) was grown as intercrop during the Cyamopsis tetragonolobakharifA. excelsa seasons of 2018 and 2023. At 24 months after planting (MAP), trees were significantly taller and thicker in wider spacings of 6m × 6m and 8m × 8m compared to closer spacing of 4m × 4m; while in P. cineraria, different spacings did not significantly affect tree height and collar diameter. In this period, collar diameter and height of increased by 10.9 and 6.9-fold in 6m × 6m and 9.9 and 6.8-fold in 8m × 8m A. excelsaspacing, respectively. Percent increment in tree growth parameters were higher during initial growth period (6-12 MAP), and decreased in the subsequent months for both . Among the different A. excelsa and P. cinerariaspacings, higher percent increment in collar diameter in both the species at 24 MAP was recorded in 6m × 6m spacing. The intercrop yield in both the years was not significantly affected by different tree species and spacings. The study indicated that could be established and grown faster in arid region at wider A. excelsaspacings to get maximum tree growth

Comparison of Physiological, Anatomical, and Morphological Traits between Sugarcane Hybrids and Their Parents with Different Stalk Dry Weights in the Early Growth Stage under Hydroponic Conditions

The high stalk weight sugarcane cultivar has a special mechanism to obtain greater growth, which was inherited from its parents. Thus far, comparisons of the high stalk weight sugarcane cultivar growth with its parents and cultivars with a low stalk weight have never been reported. The purpose of this research was to reveal the growth mechanism of the high stalk dry weight cultivar KK3 by comparing its physiological, anatomical, and morphological traits to those of a low stalk dry weight cultivar (UT12) and their four parental cultivars under hydroponic conditions. Their growth characteristics were evaluated at 15-day intervals from 30 to 90 days after planting. The root traits were measured at 2 months after planting (MAP), whereas the anatomical and physiological parameters were collected at 3 MAP. Biomass was recorded at 1, 2, and 3 MAP. KK3 had similar anatomical root traits to its female parent, whereas it had similar aboveground morphological traits to its male parent. The comparison between UT12 and its parents revealed that almost all its root anatomical traits were similar to the female parent, but it did not differ in leaf anatomy and root system size. Some physiological traits of KK3 were not different from those of its parents. In contrast, the net photosynthesis rate (PN), height, tiller number, stem dry weight, and stomatal density of UT12 were lower than those of its parent. For KK3, its small root stele and vessel size and high root length, surface area, and volume supported water uptake. The increase in stomatal density and decreased stomatal pore length may be appropriate characteristics for reducing water loss in this drought-resistant cultivar. Furthermore, KK3 exhibited a high water use efficiency (WUE) to promote biomass accumulation and growth despite its low transpiration and photosynthesis rates. This basic knowledge will be useful for selecting the parents based on their characteristics to create new sugarcane cultivars with a high stalk dry weight for drought stress during the early-growth-stage breeding programs and predicting their performance.

Effect of Ethrel as a Flower Induction Agent on the Growth and Quality of Fresh Golden Pineapple (MD2) in Malaysia

Ethrel was proposed as a good flowering agent to induce the flowering of various fresh pineapples. However, very limited research studies have been carried out on the effect of this inducing agent on the growth of the golden pineapple or Millie Dillard (MD2) in Malaysia, with none in Sarawak. To address this research gap, this study aims to investigate the effect of ethrel on the growth and fruit quality of MD2 pineapples growth in Miri, Sarawak. In this study, ethrel acts as an induction agent that was applied to induce the pineapples at maturity around 11 months after planting (MAP). Moreover, these induced pineapples were harvested 15 MAPs, whereas no pineapples were available for harvesting from the control group that was induced by natural flowering. These results showed that ethrel provided a higher yield in the number of pineapples compared to natural flowering, classifying them as Grade B pineapples. For the growth and fruit quality of the MD2 pineapples, it was found that the average values for the total soluble solids (TSS), total titratable acidity (TTA), pH, diameter, height with a crown, and whole fruit fresh weights with the crown of the pineapples were 16.48 Brix, 0.54 %, pH 3.89, 11.7 cm, 40.3 cm, and 1.4 kg, respectively. Furthermore, the average TSS to TTA ratio was 32.52, which was within the range of 5.5 to 66.4, indicating that the pineapples were sweet with prospects for commercial selling. Hence, it can be concluded that using ethrel as an induction agent is significant in Malaysia.

Influence of Field and Storage Diseases and Pests on Tuber Yield and Quality of Exotic and Local Yam (Dioscorea spp.) Genotypes

Field and storage trials were conducted to assess the response of exotic and local yam genotypes to major diseases (anthracnose, yam mosaic virus (YMV) and dry rot) and pests (i.e., mealy bug and nematodes) for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Njala Agricultural Research Centre (NARC) experimental site in Sierra Leone during two cropping seasons, 2020 and 2021. A total of 113 genotypes of yam comprising 15 D. rotundata, 4 D. prahensilis, 7 D. esculenta, 74 D. alata, 7 D. bulbifera, and 4 D. cayenensis were assessed. Results showed a significant (p &lt; 0.001) linear relationship between yield and disease severity among yam genotypes. In-field disease (anthracnose and yam mosaic virus) infection accounted for 38% of the total variation observed in the fresh tuber yield. Findings on fresh tuber yield revealed that for every ton increase in yield of yams, anthracnose and YMV severities at five months after planting (MAP) decreased by 0.5 and 3.1 units, respectively. About 30 genotypes had low infection of disease, of which two belonged to D. rotundata (TDr 205 and TDr 96/00587), two belonged to D. prahensilis (PSLY074-13 and BMSLY085-13), three belonged to D. bulbifera (MOSLY022-12, MOSLY024-12 and KESLY09-12), and one belonged to D. esculenta (WRSLY083-13), while the remaining were D. alata. About 27 genotypes had intermediate infection, and 14 had high disease susceptibility, all of which belonged to D. alata. Storage disease infection had a highly significant (p &lt; 0.002) linear relationship among yam genotypes. Dry rot, mealy bug, and nematode infection accounted for 15.1% of the total variation in fresh tuber weight loss. The findings were relevant for selecting parents with complementary traits of interest targeted at yam population improvement.

Metabolite fingerprinting of cassava (Manihot esculenta Crantz) landraces assessed for post-harvest physiological deterioration (PPD).

Cassava landraces are impacted by post-harvest physiological deterioration (PPD). 34 primary/secondary metabolites (carotenes, flavonols, indols, phenolic, hydroxycinnamic, and organic acids) were analysed using HPLC/GC-MS in 72 landraces harvested 8months after planting (MAP) to clarify whether these compounds may play a role in PPD tolerance. Cluster analysis differentiated a first group with high organic acids contents, citric acid being dominant, a second group with landraces high in tryptophan, a third group including landraces with high phenolic and hydroxycinnamic acids content, and a fourth group characterised by 8 carotenoids. PPD tolerant and susceptible landraces were present in each group. To determine if PPD is related to age of harvest, 174 landraces were harvested at 6, 8, 10 and 12 MAP. Scopoletin, sucrose and glucose were analysed. PPD was positively correlated with DMC and negatively correlated with scopoletin at all ages of harvest. Scopoletin is a useful biomarker to characterize landraces.