Efektivitas Cyhalofop-butyl Mengendalikan Gulma pada Budidaya Padi Sawah Tabela

High competition in the early growth phase will suppress growth and reduce rice yields. Presence of weeds in the rice field ecosystem needs to be controlled. Weed control with herbicides is more effective than other controls. This study aims to determine the effectiveness of the herbicide Cyhalofop-butyl in controlling weeds in the cultivation of direct seeds rice cultivation. The research was conducted in Sekaran village, Wonosari sub-district, Klaten district, Central Java. The method used was randomized block with seven treatments and four replications. The treatment consisted of a dose of the herbicide Cyhalofop-butyl 100 g.L^-1with levels: (50, 75, 100, 125, 150, and 175 L.ha^-1), mechanical weeding and control (no weeding). The results showed that Cyhalofop-butyl at a dose of 50–175 L.ha^-1 was effective in controlling the weeds of <em>Echinochloa crus-galli, Leptochloa chinensis</em> and other weeds at 3 weeks after application up to 6 weeks after application, without causing phytotoxicity effect on rice plants, herbicide Cyhalofop-butyl does not affect the growth and production of rice but reduces competition between weeds and rice plans. Herbicide Cyhalofop-butyl applied at a dose of 50 - 175 L.ha^-1provide rice grain yield of 10,25 - 11,50 kg per plot.

Superabsorbent Polymer Seed Coating Reduces Leaching of Fungicide but Does Not Alter Their Effectiveness in Suppressing Pathogen Infestation

Superabsorbent polymers (SAPs) applied to soil have been recognized as water reservoirs that allow plants to cope with periods of drought. Their application as a seed coat makes water available directly to the seeds during their germination and early growth phase, but on the other hand, it can affect the efficiency of plant protection substances used in seed dressing. In our experiments, we evaluated the effect of seed coating with SAP on fungicide leaching and changes in their effectiveness in suppressing Fusarium culmorum infestation. Leaching of fungicide from wheat seeds coated with SAP after fungicide dressing, as measured by the inhibition test of mycelium growth under in vitro conditions, was reduced by 14.2–15.8% compared to seeds without SAP coating. Germination of maize seeds and growth of juvenile plants in artificially infected soil did not differ significantly between seeds dressed with fungicide alone and seeds treated with SAP and fungicide. In addition, plants from the seeds coated with SAP alone grew significantly better compared to untreated seeds. Real-time PCR also confirmed this trend by measuring the amount of pathogen DNA in plant tissue. Winter wheat was less tolerant to F. culmorum infection and without fungicide dressing, the seeds were unable to germinate under strong pathogen attack. In the case of milder infection, similar results were observed as in the case of maize seeds.

Screening of Mungbean Accessions Under Salinity Stress

Experiments were conducted to identify suitable agro-morphological indicators of salinity tolerance and to classify fifty mungbean accessions into different salt tolerant groups by screening under different NaCl solution in pot culture in green house condition for two growing seasons. Results reveled that the early growth phase of mungbean is highly affected due to salinity and the interrelationship between salinity and accessions was also statistically significant for yield parameters under different levels of salinity stress. Salt tolerant accessions were less affected at high salinity and could be produced better total dry matter as compared to others. On the basis of relative total dry matter (RTDM%), accessions were categorized as highly tolerant, moderately susceptible and highly susceptible. G4 was found to be the best tolerant line after considering both the seasons and all the tested parameters. Correlation study suggested that germination was least affected while seedling length, pod and seed yield severely fractured due to salinity. These desirable parameters may take part in future breeding programme as salinity indicators and also by getting introduced into the susceptible lines, whereas, the tolerant accessions can be introduced as tolerant checks. Bangladesh J. Bot. 50(3): 475-482, 2021 (September)

ATP-dependent protease ClpP and its subunits ClpA, ClpB, and ClpX involved in the field bismerthiazol-resistance in Xanthomonas oryzae pv. oryzae

Resistance of Xanthomonas oryzae pv. oryzae (Xoo), which causes rice bacterial leaf blight, to bismerthiazol has been detected in China since the 1990s. Interestingly, the strains resistant to bismerthiazol on rice plants were more sensitive to bismerthiazol than wild-type (WT) strains in vitro. Here, qPCR was applied to detect the fold expression of ATP-dependent proteases, ClpP and its subunits, which cope with stresses including bactericides in bismerthiazol-resistant strains and their parental susceptible WT strain (ZJ173). Results showed that the expression of ClpP and its subunits were all higher in bismerthiazol-resistant strains than that in ZJ173. They were up-regulated during early growth phase and down-regulated during middle growth phase in ZJ173 treated with bismerthiazol but did not change in the resistant strains. ClpP and its subunits were overexpressed in Xoo in this study, the higher expression of these genes increased sensitivity in vitro and enhanced resistance in vivo to bismerthiazol. Inhibition of bismerthiazol to exopolysaccharide production, biofilm, and motility was also reduced in ClpP and its subunit’s overexpression mutants of Xoo. The deletion mutants of ClpP and its subunits in ZJ173 abated pathogenicity, biofilm production, swimming ability, exopolysaccharide production, and growth in low-nutrient environments. Moreover, ClpP and its subunits may act downstream of the histidine utilization pathway, which could be inhibited by bismerthiazol in Xoo. Taken together, our results indicated that ClpP and its subunits of Xoo influenced the resistance to bismerthiazol.

Pengaruh Ekstrak Gulma dan Bahan Alami Terhadap Perkecambahan Jagung

<p>The presence of weeds in the crop can become a competitor and reduce crop production. Each type of weed and naturally materials contains different allelochemical compounds. This research aims to create appropriate technology for weed management in maize cultivation, especially in the early growth phase (germination) so that it can suppress the effect of weeds at the beginning of growth and increase maize growth. The research used a completely randomized design (CRD) with 8 treatments namely aquadest (without weed extract/control), extract of the weed in the teki groups (<em>Cyperus rotundus</em>), grass weeds (<em>Dactyloctenium aegyptium</em>) and wide leaf weeds (<em>Euphorbia heterophylla</em>), ketapang, beluntas, acacia, and ginger (<em>Zingiberaceae</em>). The results showed that weed extract of <em>D. aegyptium</em> gave the greatest effect of inhibition of germination compared to <em>C. rotundus</em> and <em>E. heterophylla</em> at 12 DAS. Ginger leaf extract (<em>Zingiberaceae</em>) had the greatest effect on inhibition of germination compared to ketapang, beluntas, and acacia on corn seeds at 7 DAS. The application of weed extracts and natural ingredients can have an inhibitory effect, especially on the growth phase, namely the maize germination phase.</p>

Study on Vegetative Propagation of Elionurus latiflorus (Nees Ex Steud.) Hack

Aims: Elionurus latiflorus (Nees ex Steud.) Hack. commonly known as Brazilian lemongrass is a medicinal plant native to Brazil. Present experiment was conducted to study the effect of number of tillers/vegetative unit of transplants on biomass production in a period of 480 days. Study design: The experiment was conducted by using completely randomized design with three treatments i.e. plants transplanted with one tiller (T1), plants transplanted with 2 tillers (T2) and plants transplanted with 3 tillers (T3). These treatments were replicated eight times where transplantations were done in polybags which containing mixture of soil, dung and carbonized rice in 3:1:1 ratio. These polybags were kept for 160 days in greenhouse and pruning was done in every plant by maintaining 5 cm of the plant biomass for its regrowth. Duration of Study: This experiment was carried out over 16 months. Methodology: Every plant seedling was submitted to a cut maintaining approximately 5 cm of the plant biomass for its regrowth. After each pruning, survival percentage, increment in the number of tillers propagated, rise of plants height, fresh as well as dry mass weight were evaluated. Results: Lower initial number of main stems influenced survival only in the early growth phase after transplantation with a loose of 73% of the population transplanted with an unique main stem. Survival kept a constant value without plant mortalities in the successive 320 days evaluated after the first pruning. The number of tillers propagated weren’t affected significantly by the number of initial main stems in a single period. In the other hand, in the comprehensive period of the experiment there was a change with mean variation from 9.68 to 36.75. Height decreased the mean from 102.82 cm to 26.66 cm. Fresh and Dry Plant Mass increased from 5.19 g/plant to 11.47 g/plant and from 2.17 g/plant to 4.93 g/plant respectively, P˂0.05. Conclusion: This study even if elementary represents a required approach for the domestication of the species avoiding the waste of time and plant material for successive propagation works. It represents a suggestion for further research work in greenhouses with this specie for a validation of these results.

Komposisi Larva Ikan pada Ekosistem Lamun di Perairan Jepara Jawa Tengah

Larva merupakan fase pertumbuhan awal pada ikan, pada fase tersebut ikan-ikan membutuhkan tempat untuk berlindung dan mencari makanan. Ekosistem lamun sangat mendukung keberlangsungan hidup ikan, fungsi ekologis lamun sebagai daerah memijah, daerah asuhan serta tempat mencari makan bagi ikan. Tujuan penelitian ini untuk mengetahui kehadiran, serta mengetahui hubungan antara kelimpahan larva ikan dan lamun di Perairan Prawean dan Blebak, Kabupaten Jepara. Metode yang digunakan dalam penelitian ini adalah metode deskriptif dan penentuan lokasi sampling menggunakan purposive sampling methode. Penelitian ini dilakukan pada dua lokasi yang berbeda dengan masing-masing lokasi memiliki 2 stasiun, pada setiap stasiun memiliki 3 stasiun. Pengambilan sampel larva ikan dilakukan dengan menggunakan larva net (P = 0,9 m; L : 0,6 m) dengan ukuran mata jaring 800 µm. Sampel yang didapat kemudian disortir dan diidentifikasi menggunakan literatur. Hasil penelitian ini ditemukan Nemipteridae, Lutjanidae, Ambassidae, Sphyraenidae, Bothidae, Clupeidae, Chanidae, Monacanthidae. Famili larva ikan yang dominan adalah Nemipteridae. Nilai indeks keanekaragaman dari empat stasiun termasuk dalam kategori rendah-sedang (0,92 - 1,50). Nilai indeks keanekaragaman dari empat stasiun termasuk dalam kategori sedang-tinggi (0,61 - 1,00). Kisaran nilai indeks dominasi larva ikan dari empat stasiun menunjukan tidak adanya famili yang mendominasi (0,23 - 0,54). Larvae are an early growth phase in fish, in that phase fish need a place to take shelter and find food. Seagrass ecosystem strongly supports the survival of fish, the ecological functions of seagrass as a clusters area, an area of care and a place to eat for fish. The purpose of this research is to know the presence, and know the relationship between the abundance of fish larvae and seagrass in Prawean waters and Blebak, Jepara regency. The method used in this research is the descriptive method and determination of location sampling using purposive sampling Methode. The research was conducted on two different locations with each location having 2 stations, at each station having 3 substations. Sampling of fish larvae is done using the net larva (P = 0.9 m; L: 0, 6m) with mesh eye size 800 μm. The obtained samples were then sorted and identified using literature. The results of this study were found in the larvae of 8 families Nemipteridae, Lutjanidae, Ambassidae, Sphyraenidae, Bothidae, Clupeidae, Chanidae, Monacanthidae. The family of fish larvae most commonly found are Nemipteridae. The value of the diversity index of the four stations is included in the low-medium category (0.92 - 1.50). The value of the diversity index of four stations is included in the medium-high category (0.61 - 1.00). The value of the index of the dominance of the fish from the four stations indicates that there is no dominant family (0.23 - 0.54).

Skipping the Insect Vector: Plant Stolon Transmission of the Phytopathogen ‘Ca. Phlomobacter fragariae’ from the Arsenophonus Clade of Insect Endosymbionts

The genus Arsenophonus represents one of the most widespread clades of insect endosymbionts, including reproductive manipulators and bacteriocyte-associated primary endosymbionts. Two strains belonging to the Arsenophonus clade have been identified as insect-vectored plant pathogens of strawberry and sugar beet. The bacteria accumulate in the phloem of infected plants, ultimately causing leaf yellows and necrosis. These symbionts therefore represent excellent model systems to investigate the evolutionary transition from a purely insect-associated endosymbiont towards an insect-vectored phytopathogen. Using quantitative PCR and transmission electron microscopy, we demonstrate that ‘Candidatus Phlomobacter fragariae’, bacterial symbiont of the planthopper Cixius wagneri and the causative agent of Strawberry Marginal Chlorosis disease, can be transmitted from an infected strawberry plant to multiple daughter plants through stolons. Stolons are horizontally growing stems enabling the nutrient provisioning of daughter plants during their early growth phase. Our results show that Phlomobacter was abundant in the phloem sieve elements of stolons and was efficiently transmitted to daughter plants, which rapidly developed disease symptoms. From an evolutionary perspective, Phlomobacter is, therefore, not only able to survive within the plant after transmission by the insect vector, but can even be transmitted to new plant generations, independently from its ancestral insect host.

Survivability of pure and cross bred chickens at early and late growth phases in Nigeria humid tropics

Survival is a general measure of an animal's fitness. In commercial poultry production, mortality can result from a range of conditions (disease, physiological stress, environmental condition and aggressive behaviour. This study was aimed at evaluating Yoruba Ecotype Chicken (YEC), Sussex (SS), Goliath (GG), Marshall (MM) and their crossbred offspring for survivability in the Nigeria humid tropical climate. A total of 529chicks were raised fromday-old to 8 weeks (early growth phase) and 9 weeks to 20 weeks of age (Late growth phase). Data obtained were subjected to the Kaplan meier survivability test using SPSS (2012) version 21. The findings of the study revealed that at early growth phase, pure bred YEC x YEC had highest survivabilityof 91.20% while crossbred YEC x GG had the least survivability rate of 75.00%. The overall survivability of 86.40% was recorded at this stage. Late growth phase recorded highest survivability (100%) for cross bred YEC x GG while cross bred YEC x MM had the least survivability of 87.50% while the overall survivability was 94.10%. This study concluded that YEC are hardy compared with other genotypes, especially at the early growth phase while cross breeding improved the performance of YEC x GG at the late growth phase. The study recommends that YEC should be used as terminal sire in crosses involving exotic breeds for proper adaptability and performance in the Nigeria humid tropics.

Turning Up the Temperature on CRISPR: Increased Temperature Can Improve the Editing Efficiency of Wheat Using CRISPR/Cas9

The application of CRISPR/Cas9 technologies has transformed our ability to target and edit designated regions of a genome. It’s broad adaptability to any organism has led to countless advancements in our understanding of many biological processes. Many current tools are designed for simple plant systems such as diploid species, however, efficient deployment in crop species requires a greater efficiency of editing as these often contain polyploid genomes. Here, we examined the role of temperature to understand if CRISPR/Cas9 editing efficiency can be improved in wheat. The recent finding that plant growth under higher temperatures could increase mutation rates was tested with Cas9 expressed from two different promoters in wheat. Increasing the temperature of the tissue culture or of the seed germination and early growth phase increases the frequency of mutation in wheat when the Cas9 enzyme is driven by the ZmUbi promoter but not OsActin. In contrast, Cas9 expression driven by the OsActin promoter did not increase the mutations detected in either transformed lines or during the transformation process itself. These results demonstrate that CRISPR/Cas9 editing efficiency can be significantly increased in a polyploid cereal species with a simple change in growth conditions to facilitate increased mutations for the creation of homozygous or null knock-outs.