Plant Tiller Research Articles

A comparative study of yield and quality of local Karacadag and Osmancik-97 in conventional and organic agricultural conditions

The work was carried out to compare the yield and quality of local Karacadag rice variety with the Osmancık-97 in conventional and organic agriculture conditions. In the organic agricultural conditions higher values were obtained compared to conventional conditions. Flowering took 82.6 days, 1000-kernel weight (31.38 g) and non-fractured rice yield were 61.75%. Local Karacadag rice variety under the organic conditions showed significantly higher values compared to Osmancık-97 breeding variety took 87.3 days for flowering, 128.2 days for ripening days. Plant height (84.1 cm), number of tillering in plants (2.82), number of bunches in the m2 (369.3), kernel number of bunch (56.5), bunch length (15.9 cm), biological yield (13440 kg/ha), yield for unit area (4681 kg/ha) and non-fractured rice yield (64.7%) were observed. While there was no difference between the two rice varieties with regards to the kernel weight of bunch. Local Karacadag variety proved its ability to adapt to the ecological conditions of the region. It is suggested that the cultivation of the Karacadag rice cultivar in organic agriculture conditions may be expanded in the region.

Combined Effect of Ferrous Ion and Biochar on Cadmium and Arsenic Accumulation in Rice

Excessive accumulation of cadmium (Cd) and arsenic (As) in rice (Oryza sativa L.) poses a potential health risk to populations. Cd and As exhibit opposite geochemical behavior in paddy soil, using appropriate remediation materials to reduce their migration and inhibit their uptake by rice is a great challenge. A pot culture experiment was conducted to investigate the effects of application of silkworm excrement biochar (BC) and ferrous sulfate (Fe(II)) on available Cd and As in paddy soils and their uptake by rice. Results showed that the application of BC + Fe significantly accelerated the tillering of rice plants, and the addition of BC alone to soil did not have a significant effect on the pH of soil, while applied 1% (w/w) BC and 1% (w/w) Fe(II) (1BC-1 Fe(II)) treatment could markedly reduce the soil pH. BC+Fe(II) could reduce the content of available Cd (reduced by 10%–23%) and As (reduced by 6%–33%) in soil. BC+Fe(II) has a distinct decreasing effect on the available As, thus inhibiting As uptake in rice tissues, and the effect was more obvious with an increasing mass ratio of Fe in BC+Fe(II) treatment. BC+Fe(II) decreased bioaccumulation factors (BF) of As compared to control and BC alone treatments. Compared with As, Cd was more readily transferred from the root to the shoot and accumulated in rice eventually. These findings provide a safe and reliable remediation strategy though application of BC+Fe(II) in Cd and As co-contaminated soil. However, the improvement effect of amendments should be paid a special attention on soil pH.

Formation of spring barley grain yield and its structure depending on the variety and nutrition conditions in the Southern Steppe of Ukraine

Theresearch results are presented conducted during 2016-2018 on southern chernozem with two varieties of spring barley to study the impact of nutrition optimization on grain yield and elements of its structure. It is determined that the treatment of crops with growth regulating drugs in the main growing seasons provides a significant increase in grain productivity of barley, which is the highest when formed by three foliar nutrition with modern growth regulating drugs in the tillering phase and plant emergence in the tube at the beginning of earing. The grain yield of spring barley of the Stalker variety increased on average over three years, depending on the growth regulator taken for processing, in the range of 3.25 – 3.60 t / ha at its level in control, respectively, for treatment of plants with water 2.50 t / ha, and the variety Vakula – to 3.41 – 3.71 compared with 2.47 t / ha in the control. It was found that the increase in grain yield by the studied varieties of spring barley was due to the increase in ear length, and most significantly – due to more grains in the ear, the weight of grain from the ear and the weight of 1000 grains. These indicators increased and changed under the influence of power optimization. Key words: spring barley, varieties, elements of crop structure, grain yield, foliar fertilization, growth regulators.

Transcriptomic and Co-Expression Network Profiling of Shoot Apical Meristem Reveal Contrasting Response to Nitrogen Rate between Indica and Japonica Rice Subspecies.

Reducing nitrogen (N) input is a key measure to achieve a sustainable rice production in China, especially in Jiangsu Province. Tiller is the basis for achieving panicle number that plays as a major factor in the yield determination. In actual production, excessive N is often applied in order to produce enough tillers in the early stages. Understanding how N regulates tillering in rice plants is critical to generate an integrative management to reduce N use and reaching tiller number target. Aiming at this objective, we utilized RNA sequencing and weighted gene co-expression network analysis (WGCNA) to compare the transcriptomes surrounding the shoot apical meristem of indica (Yangdao6, YD6) and japonica (Nipponbare, NPB) rice subspecies. Our results showed that N rate influenced tiller number in a different pattern between the two varieties, with NPB being more sensitive to N enrichment, and YD6 being more tolerant to high N rate. Tiller number was positively related to N content in leaf, culm and root tissue, but negatively related to the soluble carbohydrate content, regardless of variety. Transcriptomic comparisons revealed that for YD6 when N rate enrichment from low (LN) to medium (MN), it caused 115 DEGs (LN vs. MN), from MN to high level (HN) triggered 162 DEGs (MN vs. HN), but direct comparison of low with high N rate showed a 511 DEGs (LN vs. HN). These numbers of DEG in NPB were 87 (LN vs. MN), 40 (MN vs. HN), and 148 (LN vs. HN). These differences indicate that continual N enrichment led to a bumpy change at the transcription level. For the reported sixty-five genes which affect tillering, thirty-six showed decent expression in SAM at tiller starting phase, among them only nineteen being significantly influenced by N level, and two genes showed significant interaction between N rate and variety. Gene ontology analysis revealed that the majority of the common DEGs are involved in general stress responses, stimulus responses, and hormonal signaling process. WGCNA network identified twenty-two co-expressing gene modules and ten candidate hubgenes for each module. Several genes associated with tillering and N rate fall on the related modules. These indicate that there are more genes participating in tillering regulation in response to N enrichment.

Influence of Plant Spacing and Phosphorus Rates on Yield Related Traits and Yield of Faba Bean (Viacia faba L.) in Duna District Hadiya Zone, South Ethiopia

A field experiment was conducted to study the effects of plant spacing and phosphorus rates on yield related traits and yield of faba bean (Viacia faba L.) at Farmers Training Center, Duna District during 2015 summer cropping season. Three intra-rows spacing (5, 10 and 15 cm), three inter-rows spacing (30, 40 and 50 cm) and three phosphorus rates (0, 46 and 92 kg/ha) were tested. The experiment was laid out as a randomized complete block design (RCBD) and was replicated three times. Improved faba bean variety (Degaga) was ued as test crop. Phenological growth parameters yield and yield related data were collected and their ANOVA was analyzed using GenSta 5th edition and while treatment means were significantly different, they were separated using Least Significant Difference (LSD) at 5% probability level. There was highly significant (P<0.01) effect of the highest rate of phosphorus (92 kg P2O5 ha-1) on days to flowering, days to maturity, leaf area index, effective nodules per plant, plant height , primary tillers plant-1, seeds pod-1, hundred seed weight, grain yield, above ground dry biomass and harvest index. Significantly lowest days to flowering (54.3 days) after emergence and highest plant height (105.63 cm), leaf area (1073 cm2), seeds pod-1(3.57), grain yield (2633 kg ha-1), dry biomass (8108kg ha-1) and harvest index (32.47) were obtained from the highest rate of P (92 kg P2O5 ha-1). For all inter-rows spacing, the leaf area, number of primary tillers, pods plant-1, seeds pod-1 and hundred seed weight were increased as intra-row spacing increase and the highest leaf area (1084 cm2), primary tillers (2.99) and hundred seed weight (54.59 g) were obtained from the widest (50 cm) inter-row spacing, while the highest effective nodules (59.56) and leaf area index (3.51) were resulted from the narrowest (30 cm) inter-row spacing. On the other hand, the interaction effects of inter and intra-row spacing significantly influenced, number of pods plant-1, number of seeds pod-1, above ground dry biomass, grain yield and harvest index. The 30 cm inter-row by 15 cm intra-row spacing gave the highest grain yield (2495 kg ha-1), harvest index (35.79%) and pods plant-1(19.68) whereas the highest dry biomass (8738 kg ha-1) was obtained from 30 cm x 5 cm spacing combination. Thus, it can be concluded that application of 92 kg P2O5 ha-1 rate of phosphorus at 30 x 15 cm spacing combination proved to be superior with respect to grain yield in the study area. However, further study at least for one more cropping season under different soils is required to reach at conclusive recommendation.

THE ADAPTATION LEVEL OF ALFALFA (MEDICAGO SATIVA L.) THAT IRRADIATED WITH GAMMA RAYS ON A FIELD SCALE

Alfalfa (Medicago sativa L.) a high nutritious and palatability legume for ruminant. Constrain of alfalfa availability in Indonesia are due to the plant adaptability in tropical environment. Aim of the study was to measure the adaptation level of alfalfa that irradiated with gamma rays on a field scale. The study consisted of four types of plant sources, mutation plants with different gamma ray levels (0Gy, 200Gy, 300Gy and 400Gy). Plant tillers was analyzed with a complete randomized design with 3 replications, 20 plants per replication. Growth capability, leaf color, flowering time and pest attack level were analyzed descriptively. The results showed that alfalfa irradiated with 300 Gy significantly (p<0.05) produced highest tillers. Irradiated 300 Gy plant gave better result on growth capability, flowering capability, and number of not attack plant from pests. The higher level of gamma ray irradiation showed the changed in leaf color levels from dark green to light green.
 Keywords: alfalfa (Medicago sativa L.), mutation, gamma ray irradiation, field scale

Genomic evidence of human selection on Vavilovian mimicry.

Vavilovian mimicry is an evolutionary process by which weeds evolve to resemble domesticated crop plants and is thought to be the result of unintentional selection by humans. Unravelling its molecular mechanisms will extend our knowledge of mimicry and contribute to our understanding of the origin and evolution of agricultural weeds, an important component of crop biology. To this end, we compared mimetic and non-mimetic populations of Echinochloa crus-galli from the Yangtze River basin phenotypically and by genome resequencing, and we show that this weed in rice paddies has evolved a small tiller angle, allowing it to phenocopy cultivated rice at the seedling stage. We demonstrate that mimetic lines evolved from the non-mimetic population as recently as 1,000 yr ago and were subject to a genetic bottleneck, and that genomic regions containing 87 putative plant architecture-related genes (including LAZY1, a key gene controlling plant tiller angle) were under selection during the mimicry process. Our data provide genome-level evidence for the action of human selection on Vavilovian mimicry.

Charcoal and compost application induced changes in growth and yield of Wheat (Triticum aestivum L.)

The utilization of organic fertilizers in farmlands to enhance crop productivity and soil health is increasing globally. Compost and charcoal obtained from the decomposition and slow pyrolysis (respectively) of plants and animals wastes. Here we evaluated the effect of charcoal and compost on the growth and yield of wheat (Triticum aestivum L.) at Agriculture Research Farm Peshawar, Pakistan during 2014-2015. Results showed that the application of compost and charcoal as sole or in combination significantly affected the yield and yield attributes of wheat. Data divulged that the maximum numbers of plant tillers (337 m-2), number of productive tillers per plant (313 m-2), number of grains per spike (56 spike-1) and 1000 seeds weight (50.2 g) were produced by the combined application of compost and charcoal at 5+5 Mg ha-1 while plant height (95.3 cm) was enhanced with the application of charcoal at 10 Mg ha-1. The gain (4106.7 kg ha-1) and biological yield (8473.3 kg ha-1) was significantly increased with the compost application at the rate of 10 Mg ha-1. These results proved that charcoal and compost can be used as organic fertilizers for boosting growth and yield performance of wheat under the agro-climatic conditions of Peshawar, Pakistan.

AUTUMN GROWTH AND DEVELOPMENT OF WINTER WHEAT PLANTS ON THE IRRIGATED LANDS DEPENDING ON HYDROTHERMAL CONDITIONS, VARIETIES AND TERMS OF SOWING

Actuality. For the last few years the instability in grain productions in the Steppe zone has been observed that is mainly connected with the fluctuations of agrometeorological conditions and global climatic change. Climate change made corrections in terms of sowing of winter crops, which are one of the main factors of technological process, which productivity of the crops depends on. Goal. To determine the influence of agrometeorological conditions, varieties and terms of sowing on the growth and development of plants during the autumn period of vegetation when cultivating winter wheat varieties on irrigated lands. Methods. The researches were conducted at the Institute of Irrigated Agriculture NAAS using the methodology of field and laboratory experiments on irrigated lands (IOZ NAAS, 2014). Results. During the study period it was determined that the hydrothermal conditions and the duration of the autumn period for winter wheat vegetation were significantly different. When sowing on the 20th of September, on the 1st of October, and on the 10th of October, the duration of the autumn vegetation period in 2016 was 56, 46 and 36 days, in 2015 - 100, 90 and 80 days and in 2017 - 114, 104 and 94 days respectively. When sowing on the 20th of October, winter wheat plants vegetated during 26, 70 and 84 days, respectively. Sowing terms affected winter wheat sprout population in different ways - when sowing on the 20th of September, it averaged to 372 plants/m2, on the 1st of October - 407 plants/m2, on the 10th of October – 386 plants/m2 and on the 20th of October - 392 plants/m2. It was determined that at different terms of sowing the plants entered in winter period with uneven growth and development. When sowing on the 20th of September all the varieties in autumn tillered, and in average for three years they created 4.1-5.0 shoots, developed more herbage mass of 713-761 g/m2 in comparison to other terms of sowing. The later wheat was sown, the less the plant tillering was, therefore, less herbage mass was formed. Conclusions. Agrometeorological conditions of autumn period and terms of sowing significantly affect the population of sprouts and growth processes of the plants of current winter wheat varieties. The highest plant population of all the varieties was formed when sowing on the 1st of October, the least one was formed by the varieties Mariia and Kokhana at early sowing on the 20th of September, and variety Ovidii – at early sowing on the 20th of September, and at late sowing on the 20th of October. That is, the Ovid variety is more responsive to the terms of sowing and to the deviation from the optimal (October 1) and leads to a decrease in the sprouting density. When sowing on the 20th of September and on the 1st of October all the varieties tillered intensively in autumn time, and they formed 4.1-5.0 and 3.3-3.7 shoots, respectively, developed more herbage mass comparatively to other terms of sowing - 713-761 and 313-381 g/m2 respectively. Having these terms of sowing the most intensive tillering was observed on the varieties Mariia and Kokhana, and when sowing in delayed terms no one variety had an advantage over the others.

Sugarcane Straw Blanket Management Effects on Plant Growth, Development, and Yield in Southeastern Brazil

ABSTRACTIn Brazilian sugarcane (Saccharum spp.) production systems, the practice of moving harvesting residue from row to inter‐row positions (i.e., raking) has increased in response to producer concerns over the potential negative effects of sugarcane straw on crop establishment and stalk yield. Despite increasing adoption among sugarcane farmers, the impacts of straw raking practices on plant growth and yield remain unclear. A 2‐yr experiment that included both dry and wet seasons was conducted at two sites in southeastern Brazil to evaluate straw management strategy effects on plant tillering, phytomass accumulation, plant nutritional status, and stalk yield. The experiments were established at the Bom Retiro mill and the Univalem mill. Experimental treatments included raking straw to inter‐rows (raked), total straw removal (bare soil), and no straw removal (straw cover). Raked and bare soil treatments improved plant tillering but did not influence final plant population. Straw management had a slight effect on phytomass accumulation. Reduction of phytomass yield was observed from the first to the second ratoon during both seasons at both sites. At Bom Retiro, phytomass yield decreased 37% for stands established during the dry season and 19% for stands established during the wet season. At Univalem, phytomass yield decreased 20% for stands established during the dry season and 30% for stands established during the wet season. Retaining straw in the field (regardless of treatment) increased leaf tissue P content but not stalk yield. Raking straw from row to inter‐row positions at these locations in southeastern Brazil had no benefit on sugarcane yield but may result in soil compaction and higher production costs over time.

Manganese foliar supplementation impacts rice yield in tropical lowlands

The aim of this work was to evaluate manganese (Mn) sources and levels effects in irrigated rice production in central Brasil (tropical lowlands of Tocantins state). The experiment was conducted in a 5x5 + 1 factorial scheme, five Mn sources and five levels (0.5; 1.0; 1.5; 2.0; and 2.5 kg ha−1), applied in induction of tillering of rice plants, plus a control without treatment, and Mn content in leaves (mg kg−1), number of panicles per area (m2), hundred grains weight (g), intact grains (%), and grain yield (kg ha−1) were analyzed. Treatments with Mn-carbonate source got the best results and this source at the level of 1.5 kg ha−1 provided the highest yield: 7,375 kg ha−1. Higher values were obtained with the application of 1.0 to 1.5 kg ha−1 of Mn, except for the intact grains where the best means were obtained at 2.5 kg ha−1.

Heritability estimates in F4 generation of wheat (Triticum aestivum L.) under the agro-climatic condition of Tandojam, Sindh-Pakistan

The research studies on heritability estimates were conducted to evaluate the performance of grain yield and various yield components of six F4 segregating population originated from four parental varieties of bread wheat. The experiment was conducted in Randomized Complete Block Design with 3 replications. The results for six F4 segregating populations and their four parental wheat varieties for the traits revealed highly significant differences at P< 0.01 and P< 0.05 level of probability. Different progenies showed different response for different traits. The progeny Sarsabaz x Bhittai took significantly more days to 75% maturity (128.3), more spike length (14.0 cm) and more spikelets spike-1 (21.6). Progeny Sarsabz x FD-83 showed significant increase in grain yield plant-1 (29.0g), 1000-grain weight (48.0 g) and tillers plant-1 (13.67) as compared to other progenies and the parental lines. The parent varieties Sarsabaz and Bhittai showed good performance with respect to number of tillers plant-1 (15.33) and spikelets spike-1(24.3). The progeny FD-83 x Bhittai revealed significant in number of grain spike-1 (56.7) and biological yield kg ha-1 (22960) as compared to their respective parental lines. Two progenies Nesser x Bhittai and Nesser x FD-83 showed the highest heritability coupled with more genetic advance (GA) for most of the traits measured i.e., days to 75% maturity, spike length, grains spike-1 and grain yield plant-1. Four progenies viz., Sarsabaz x Bhittai, FD-83 x Bhittai, Sarsabz x FD-83 and Nesser x Sarsabz showed better performance highest heritability associated with high genetic advance for other characters tillers plant-1, spikelets spike-1,1000-grain weight and biological yield kg ha-1. These results suggest that more effective selection could be obtained from these segregating populations for specific traits originated after these combinations. Keywords: Agro-climatic condition; Heritability; Wheat http://dx.doi.org/10.19045/bspab.2019.80066

Study of heterosis analysis in F1 population of bread wheat

The study was conducted to evaluate heterotic in bread wheat during crop season 2016-2017. Six parents of bread wheat (Triticum aestivum L.) were crossed in a half diallel design and their fifteen the first filial genration (F1s) were evaluated for heterosis for yield traits. The traits included: Days to 50% heading, Days to 75% maturity, Plant height (cm), Tillers plant-1, Peduncle length (cm), Spike length (cm), Spikelets spike-1, Grains spike-1, Grain weight spike-1 (g), Seed index (1000-grain weight, g) and Grain yield plant-1 (g). The analysis of variance due to genotypes, parents, hybrids and parents vs. hybrids were significant for all the characters which showed the presence of the significant amount of variability among parents, their hybrids and among parents vs. hybrids for all characters studied. Heterotic effects, the cross combinations such as WL-711 x Aas-2011 followed by Janbaz x Aas-2011 by expressing maximum desirable negative relative heterosis and heterobeltiosis were found advantageous for days to 50% heading and days to 75% maturity; Janbaz x Aas-2011 exhibited desirable negative heterosis for plant height; Sunco x Marvi-2000 followed by Sunco x Janbaz manifested desirable positive heterosis for tillers plant-1; Sunco x Janbaz for peduncle length, spike length and grain yield plant-1; Janbaz x Marvi-2000 for spikelets spike-1 and grains spike-1; Sunco x Pak-81 for grain weight spike-1 and seed index. The superiority of the above crosses over their better parents indicated their worth for hybrid crop development. Keywords: Bread wheat; Diallel; F1 hybrids; Heterobeltiosis; Relative heterosis http://dx.doi.org/10.19045/bspab.2019.80119

Estimation of Heritability in F2 Generation of Bread Wheat (TriticumaestivumL.)

Objectives: To estimate the heritability in a broad sense and the genetic advance F2 generation of bread wheat. Methods/Statistical Analysis: The collected data were statistically analyzed for analysis of variance by Gomez and Gomez, heritability in a broad sense and the genetic advance was worked out after Falconer. Findings: The results showed that genotypes parents, percent x crosses were highly significant at 0.01 level for days to 75% heading, days to 90% maturity, plant height (cm), tiller plant1 , spike length (cm), spikelet spike-1, grain spike-1, grain yield plant-1 (g), Biological yield and harvest index (%) while seed index (1000 grain weight, g) showed non-significant for parents vs crosses. Mean performance of six commercial and F2 hybrids revealed that early heading (62.2) presented by Kiran-95 and his F2 hybrids (59.95%), days to 75% heading taken by Benazir x TD-1, minimum days (114.8) to 90% maturity shown by variety TJ-83, dwarf plant (59.82cm) shown by variety Hamal. The maximum tiller plant-1 (13.76) produced by cross Benazir x TD-1, longer spike length (9.95cm) shown by the variety Kiran-95, while the genotype TD-1 produced maximum number of spikelet spike-1 (20.76), maximum grain spike-1 (56.03) highest grain yield plant-1 (30.53 g) and highest biological yield was obtained from the cross TD-1 x Sindhu. Highest weight for 1000-grain was recorded for TD-1, (50.20). The highest biological yield was shown by Benazir (61.03g). Among the hybrids, higher grain yield plant-1 displayed by Sindhu x Kiran-95, within the F2 population maximum harvest index of 56.45% was observed in Sindhu x TJ-83. The cross Benazir x TD-1 showed higher heritability for tiller plant-1, spike length, spikelets spike-1 and harvest index. While Benazir x Sindhu exhibited higher heritability for grain spike-1, plant height. Variety TD-1, Kiran-95, and Sindhu may be selected in further breeding programs and crossed Benazir x TD-1 could be evaluated in the subsequent generation and selection could be made on spikelets spike-1 and harvest index. Application/Improvements: The variety TD-1 performs better in spikelets spike-1, grains spike-1, grain yield plant-1, seed index, while variety Kiran-95 had higher in spike length, and harvest index. Keywords: Bread Wheat, F2 Generation, Genetic Advance, Heritability

ApoplastAssociated Bacillus methylotrophicus RABA6 Induced Growth and Yield Attributes Leading to Drought Tolerance in Rice

The present investigation was conducted with anobjective to evaluate the efficiency of anapoplastic bacterial isolate,Bacillus methylotrophicus RABA6 to alleviate moisture stress in rice variety CO51.The seeds were biotized with B. methylotrophicus RABA6, @106CFU ml-1 with an OD660 of 1.0. Irrigation was withheld for ten days during panicle initiation to impose moisture stress and biometric observations were recorded. The results showed significant differences both in vegetative growth parameters as well as yield attributes compared with the uninoculatedcontrol under moisture stress. During panicle initiation stage (85th DAS), the plant height (105.26, 104.36 cm), root length (29.57, 28.23 cm), number of productive tillers plant-1(12.34, 10.75), leaf area (1113.75, 796.52cm2 plant-1), total number of panicles/ plant (15.63, 13.69) and1000 grain weight (23.65, 22.19 g) registered more in B. methylotrophicus RABA6 inoculated plants compared touninoculated control under both irrigated and moisture stressed conditions respectively. The present study envisages that the inoculation of rice with the apoplastic bacterium B. methylotrophicus RABA6 could promote general plant health and productivityunder moisture stress. Hence,the apoplastic bacterium B. methylotrophicus RABA6 can be recommended as a bio-inoculant for alleviating drought stress in rice and reduce the dependency on chemical fertilizers thereby, providing a step forward towards sustainable agriculture.

Cloning and Expression Analysis of the ScD53 Gene from Sugarcane

D53 is a crucial gene involved in tillering regulation in crops via the strigolactone signaling pathway. The objective of our research was to clone the homologous sugarcane (Saccharum L. spp. hybrids) gene of D53 (ScD53) by in silico cloning combined with RT-PCR and rapid amplification of cDNA ends techniques, and the physicochemical properties and structure of ScD53 protein were analyzed using bioinformatic software and tools. The relationships between the expression of ScD53 and some plant hormones, bud germination and tillering occurrence of seedlings were also detected using the real-time fluorescence quantitative PCR (FQ-PCR) technique. The homolog was named ScD53 and possessed a 3918-bp cDNA sequence. Bioinformatic analysis showed that ScD53 has a complete open reading frame of 3363 bp that encodes 1120 amino acid residues. The ScD53 protein possesses the conserved domain of the P-loop NTPase and ClpB_D2-small superfamilies, which may be unstable hydrophilic proteins and are likely to be located in the nucleus. The main secondary and tertiary structures of the ScD53 protein are composed of random coil and alpha helix structures and exhibit high similarity in structure and homology with D53 proteins from sorghum [Sorghum bicolor (L.) Moench] and maize (Zea mays L.). The FQ-PCR results showed that the expression of ScD53 is tissue specific and is differently expressed in the different tissues. The expression of ScD53 is associated with bud germination, the high expression of which inhibits bud germination. Plant hormone treatment experiments indicated that the expressions of ScD53 were induced in bud and leaf tissues by strigolactones, 3-indole acetic acid and kinetin (KT, a cytokinin analog). The high expression of ScD53 following strigolactone and auxin treatment obviously delayed occurrence of tillers and reduced the number of tillers for the seedlings. However, this was not observed during KT treatment, which implied that the negative effects of this gene on seedlings tillering phenotype were eliminated by the positive influences of other unknown pathways. Our results above help elucidate the function of ScD53 and provide important information and direction for the use of this gene in improving sugarcane yield through tiller regulation.

The rice pds1 locus genetically interacts with partner to cause panicle exsertion defects and ectopic tillers in spikelets

BackgroundRice (Oryza sativa L.) is a staple food crop worldwide. Its yield and quality are affected by its tillering pattern and spikelet development. Although many genes involved in the vegetative and reproductive development of rice have been characterized in previous studies, the genetic mechanisms that control axillary tillering, spikelet development, and panicle exsertion remain incompletely understood.ResultsHere, we characterized a novel rice recombinant inbred line (RIL), panicle exsertion defect and aberrant spikelet (pds). It was derived from a cross between two indica varieties, S142 and 430. Intriguingly, no abnormal phenotypes were observed in the parents of pds. This RIL exhibited sheathed panicles at heading stage. Still, a small number of tillers in pds plants were fully exserted from the flag leaves. Elongated sterile lemmas and rudimentary glumes (occurred occasionally) were observed in the spikelets of the exserted panicles and were transformed into palea/lemma-like structures. Furthermore, more interestingly, tillers occasionally grew from the axils of the elongated rudimentary glumes. Via genetic linkage analysis, we found that the abnormal phenotype of pds manifesting as genetic incompatibility or hybrid weakness was caused by genetic interaction between a recessive locus, pds1, which was derived from S142 and mapped to chromosome 8, and a locus pds2, which not yet mapped from 430. We fine-mapped pds1 to an approximately 55-kb interval delimited by the markers pds-4 and 8 M3.51. Six RGAP-annotated ORFs were included in this genomic region. qPCR analysis revealed that Loc_Os080595 might be the target of pds1 locus, and G1 gene might be involved in the genetic mechanism underlying the pds phenotype.ConclusionsIn this study, histological and genetic analyses revealed that the pyramided pds loci resulted in genetic incompatibility or hybrid weakness in rice might be caused by a genetic interaction between pds loci derived from different rice varieties. Further isolation of pds1 and its interactor pds2, would provide new insight into the molecular regulation of grass inflorescence development and exsertion, and the evolution history of the extant rice.

Morphological diversity and correlation analysis of phenotypes and quality traits of proso millet (Panicum miliaceum L.) core collections

Genetic diversity and comprehensive performance are the basis for the discovery and efficient use of proso millet (Panicum miliaceum L.) core collections. In this study, 386 proso millet core collections were used as materials to observe inflorescence color, leaf phase, inflorescence density, axis shape, branched spike length, panicle type, trichome, measured area of the top3 leaves, and chlorophyll content of the top3 leaves at filling stage. These core collections were also used to record growth period, plant height, diameter of main stem, plant tiller number, branch number, panicle length, panicle number per plant, and panicle weight per plant at the maturation stage. Starch, fat, protein, and yellow pigment contents in the grain and 1000-seed weight were also measured after harvest. Then, quantitative traits were used for diversity analysis and comprehensive evaluation of each collection. Correlations between all traits were also analyzed. Results showed that among the 8 quality traits, the Shannon index (H′) of hull color was the highest (1.588) followed by the H′ of inflorescence density (0.984). However, inflorescence color and axis shape were lower. The H′ of 16 quantitative traits were significantly higher than the quality traits with the following traits having the highest indices: fat content (2.092), 1000-seed weight (2.073), top3 leaves area (2.070), main stem diameter (2.056), and plant height (2.052). Furthermore, all other traits had a diversity higher than 1.900. After a comprehensive evaluation of phenotypic traits, plant height, diameter of main stem, plant tiller number, leaf area of top3 leaves, and 1000-seed weight were the biggest contributors to the principal components. Six high-fat and high-protein cultivars, including Nuoshu, A75-2, Zhiduoaosizhi, Panlonghuangmi, Xiaobaishu, and Xiaohongshu were also screened. Correlations between the quantitative traits were significant, including the correlation between quality traits and quantitative traits. In conclusion, the core collections can be used as basis for discriminating among proso millet cultivars based on related traits and for further studies on millet with rich genetic diversity, good representation, and significant collection between traits.

OsCDC48/48E complex is required for plant survival in rice (Oryza sativa L.)

Key messageWe demonstrate that the C-terminus of OsCDC48 is essential for maintaining its full ATPase activity and OsCDC48/48E interaction is required to modulate cellular processes and plant survival in rice.Cell division cycle 48 (CDC48) belongs to the superfamily protein of ATPases associated with diverse cellular activities (AAA). We previously isolated a rice CDC48 mutant (psd128) displaying premature senescence and death phenotype. Here, we showed that OsCDC48 (Os03g0151800) interacted with OsCDC48E (Os10g0442600), a homologue of OsCDC48, to control plant survival in rice. OsCDC48E knockout plants exhibited similar behavior to psd128 with premature senescence and plant death. Removal of the C-terminus of OsCDC48 caused altered expression of cell cycle-related genes, changed the percentage of cells in G1 and G2/M phases, and abolished the interaction between OsCDC48 itself and between OsCDC48 and OsCDC48E, respectively. Furthermore, the truncated OsCDC48–PSD128 protein lacking the C-terminal 27 amino acid residues showed a decreased level of ATPase activity. Overexpression of OsCDC48–psd128 resulted in differential expression of AAA-ATPase associated genes leading to increased total ATPase activity, accumulation of reactive oxygen species and decreased plant tiller numbers while overexpression of OsCDC48 also resulted in differential expression of AAA-ATPase associated genes leading to increased total ATPase activity, but increased plant tiller numbers and grain yield, indicating its potential utilization for yield improvement. Our results demonstrated that the C-terminal region of OsCDC48 was essential for maintaining the full ATPase activity and OsCDC48/48E complex might function in form of heteromultimers to modulate cellular processes and plant survival in rice.

The Effects of Micronutirents on Growth and Yield of Lowland Rice Grown on Typic Dystrudept Soil

Fertilizers and fertilization technology have important roles in increasing crop production including lowland rice. In response to the issue, a field experiment was conducted to study the effects of micronutrients on growth and yield of lowland rice. The experiment was carried out at Cihideung Ilir Village, Dermaga Sub-district, Bogor Regency from November 2015 until March 2016. The experiment consisted of 8 treatments, namely control (without fertilization), NPK-standard, NPK-standard + ¼ dosage of Hortigro Rice fertilizer, and ¾ NPK + ¼ until 11/4 dosages of Hortigro Rice fertilizer as a source of macronutrients N, P, K and micronutrients of Mn, Cu, Zn, B, and Mo. The treatments were arranged in a Randomized Block Design with 3 replications. Parameters observed during the research were plant height, tiller number, and yield of grain and straw of INPARI-32 lowland rice as crop indicator. The results showed that among other treatments, the highest plant height was resulted from the application of ¾ NPK-standard + ¼ Hortigro Rice, i.e. around 124 cm at 60 days after planting. The highest harvesting dry weight of grain and straw were observed in NPK-standard + 1/4 of Hortigro Rice fertilizer treatment, i.e. around 9.0 Mg ha-1 and 25.9 Mg ha-1, respectively. This yield showed a significant difference with ¾ NPK-standard combined with ¾ -11/4 dosages of Hortigro Rice. The highest dry weight of milled grains was resulted in the application of ¾ NPK-standard + 1/2 Hortigro Rice, i.e. around 7.3 Mg ha-1, which is significantly different from that in ¾ NPK-standard combined with 1.0 - 11/4 dosages of Hortigro Rice treatments, while the highest dry weight of straw was provided by NPK-standard, i.e. around 14.0 Mg ha-1. The highest dry weight of 1000 milled grains and ratio of dry weight of milled grain to straw were provided by ¾ NPK-standard + 1/2 Hortigro Rice around 32.0 gram and 0.63, respectively. The results indicated that the application of micronutrient fertilizer of Hortigro Rice in combination with NPK fertilizers can potentially increase lowland rice productivity due to the micronutrients content of Mn, Cu, Zn, B, and Mo in it.