Sprouting and rooting ability of the plus trees of Eucalyptus pellita, E. brassiana and its hybrid in Wanagama, Indonesia

The demand for eucalypts has greatly increased since they are raw materials for timbers, plywoods, pulp and papers, and essential oil production. This study aimed to select the plus trees and determine the sprouting and rooting ability of E. pellita, E. brassiana, and their hybrids in Wanagama. Plus trees selection and girdling were conducted in December 2019. Cuttings were picked from the 3rd-4th nodes of sprouting at 8-10 cm in length. A completely randomized design was applied in a factorial experiment with three levels of Indole Butyric Acid (IBA) (100, 1000, and 4000 ppm) and two types of media (media 1: sand, rice husk charcoal and cocopeat (2:2:1), media 2: sand, topsoil and dung-fertilizer (2:2:1)), with ten replications. Results selected a total of 53 plus trees candidates (29 of E. pellita, 12 of E. brassiana, and 12 of hybrid). E. pellita is the best in sprouting ability (100% survival; 41-60 shoot/trees, 127-161cm shoot length, 0.53-0.57cm shoot diameter, and 194-252 leaves/shoot). Cuttings of E. pellita treated with 100 ppm IBA gained the highest survival and leaves production (96%-100%; 14-16 leaves), followed by E. brassiana (52%-66.67%; 7 leaves) and the hybrid (4% to 8.33%; 3-4 leaves). These results may contribute to arranging better strategies for mass production of selected eucalypts.

Genomic Adaptive Evolution of Sand Rice (Agriophyllum squarrosum) and Its Implications for Desert Ecosystem Restoration

Natural selection is a significant driver of population divergence and speciation of plants. Due to local adaptation to geographic regions with ecological gradients, plant populations harbored a wide range of adaptive genetic variation to enable them to survive the heterogeneous habitats. This is all the more necessary for desert plants, as they must tolerant more striking gradients of abiotic stresses. However, the genomic mechanism by which desert plants adapt to ecological heterogeneity remains unclear, which could help to guide the sustainability of desert ecosystems. Here, using restriction-site-associated DNA sequencing in 38 natural populations, we investigated the genomic divergence and environmental adaptation of sand rice, Agriophyllum squarrosum, an annual pioneer species that covers sand dunes in northern China. Population genetic structure analyses showed that sand rice could be divided into three geographically distinct lineages, namely, Northwest, Central, and East. Phylogeographic analyses revealed that the plant might originate locally in Bergen County and further differentiated into the East lineage and then the Central lineage. Ecological niche modeling found that different lineages occupied distinct ecological niches, suggesting that the ecological gradient would have triggered genomic differentiation among sand rice lineages. Ecological association study supported that the three SNPs under divergent selection were closely correlated with precipitation gradients, indicating that precipitation might be the most important stress trigger for lineage diversity in sand rice. These adaptive SNPs could be used to genotype suitable germplasms for the ecological restoration of specific desertified lands. Further analyses found that genetic structure could significantly overestimate the signals for balancing selection. Within the Central lineage, we still found that 175 SNPs could be subject to balancing selection, which could be the means by which sand rice maintains genetic diversity and adapts to multiple stresses across heterogeneous deserts and sandy lands. From a genomic point of view, this study highlighted the local and global adaptation patterns of a desert plant to extreme and heterogeneous habitats. Our data provide molecular guidance for the restoration of desertified lands in the arid and semi-arid regions of China and could facilitate the marker assistant breeding of this potential crop to mitigate climate change.

Soil Stabilization by using fly ash and Ferric Chloride

The soil is stabilized with fly ash and ferric chloride mixtures in this research paper. The Serviceability of the pavement is very tractable to the soil sub-grade properties. For that reason, a weaker sub-grade can be improved by using the most effective stabilization method. Based on the literature review, stabilization with fly ash activated sub grade has been found to be an effective option for improvement of soil properties. Stabilization of the soil is mostly done in soft soils such as organic soil, clayey peat, silt. Some of the wastes used are fly ash, marble dust, foundry sand, rice ash and so on. These materials not only provide an alternative to the use of conventional materials but also help control environmental pollution. In many places, the waste is dumped into the open air, which can be very problematic for the people in the area and the workers working in these areas. Using these waste materials not only reduces pollution but also reduces human credibility on natural resources, leading to a more sustainable process of construction. It was found from the literature that the optimum dose of fly ash and ferric chloride revealed essential enhancement in strength and durability characteristics and declination in the swelling and plasticity properties of the soil. Based on that result, it is suggested that a mixture of fly ash and ferric chloride should be take into consideration a workable option for the stabilization of broad subgrades.

Quality of Guava Seed (Psidium guajava L.) White and Red Varieties on Different Substrates

The guava tree is the fruit of the guava tree of the species Psidium guajava L. belonging to the family of Myrtaceae a rustic fruit and adapts to the most varied types of soils. It is a fleshy fruit, thin-skinned, green, or when mature yellowish and very rich in soluble fibers. Seed germination is influenced by factors such as substrate, which can improve germination, resulting in the acquisition of more vigorous seedlings. The experiment was conducted in a greenhouse at the Federal Institute of Education, Science and Technology of Tocantins, Gurupi/TO, in 2017. The seeds of guava Kumagai and Paluma (Psidium guajava L.) used in the experiment were taken directly from the fruit, which was collected in the urban region of Gurupi in March 2017. For the two varieties evaluated, both for the first emergence count and seedling emergence, the substrates stood out: organic compound + black earth + commercial substrate (55% and 37%) (67% and 49%), washed sand + rice straw + black earth (52% and 36%) (52% and 36 %) lower substrates: washed sand (46% and 10%) (66% and 35%) and rice straw + sawdust + black ground (47% and 7%) (59% and 31%), respectively. The substrates: organic compound + black earth + commercial substrate and washed sand + rice straw + black earth provided the highest values of viability and vigour in white and red pulp guava seeds.

PENGARUH ADANYA MATERIAL BERPORI TERHADAP KARAKTERISTIK KONSOLIDASI TANAH LEMPUNG LUNAK LAHAN BASAH

Salah satu cara untuk mempercepat aliran air maupun laju konsolidasi tanah lempung lunak lahan basah yaitu dengan menambahkan material porous didalam tanah maupun menggunakan drainasi vertical. Selama ini telah berkembang teknologi percepatan konsolidasi dengan vertical drain berbahan geosintetis. Selain berbahan geosintetis, bahan lainnya untuk material vertical drain masih terus dikembangkan untuk mencari keandalan yang ekonomis.Adapun yang menjadi permasalahan dalam penelitian ini adalah bagaimana derajat konsolidasi yang dihasilkan dari hasil pengujian konsolidasi tanah lempung lunak lahan basah yang ditambahkan adanya material berpori (berbahan pasir, sekam padi, dan arang kayu). Selain itu juga bagaimana pengaruh drainase (material berpori) radial, n (perbandingan diameter benda uji dan diameter drainase (material berpori)dari masing-masing material berpori.Dalam penelitian ini dilakukan uji konsolidasi dengan benda uji menggunakan tanah lempung lunak lahan basah. Pada bagian tengah benda uji diberi lubang berdiameter 0,75cm, 1cm, dan 1,5cm, kemudian ditambahkan material berpori berbahan pengisi berupa pasir, sekam padi, dan arang. Dari ketiga material berpori tersebut, selanjutnya akan dibandingkan sesamanya terkait kinerja material berpori sebagai sistem drainase (material berpori) didalam tanah. Hasil penelitian menunjukkan bahwa material sekam padi, pasir, dan arang dapat digunakan sebagai bahan drainase (material berpori) untuk tanah yang berkonsolidasi karena mampu meningkatkan nilai derajat konsolidasi (U%).Apabila ditinjau pada satu satuan waktu maka untuk jenis material drainase (material berpori)) berbahan sekam dapat menghasilkan derajat konsolidasi yang lebih besar dibandingkan material drainase (material berpori) berbahan pasir maupun arang.Material drainase (material berpori) berbahan sekam dapat menghasilkan nilai koefisien konsolidasi (Cv), nilai koefisien permeabilitas (k), dan nilai koefisien perubahan volume (mv) yang lebih besar dibandingkan dengan material drainase (material berpori) berbahan pasir dan arang.Nilai koefisien konsolidasi (Cv) semakin meningkat seiring dengan peningkatan nilai rasio diameter (n) hingga mencapai rasio diameter yang optimum (nopt), selanjutnya sesudah nilai rasio diameter optimum tercapai maka koefisien konsolidasi akan mengalami penurunan. Rasio diameter optimum pada tanah lempung lunak yang berkonsolidasi didapat pada nilai 6(enam).Kata kunci : Konsolidasi tanah, drainase (material berpori) vertical,derajat konsolidasi,koefisien permeabilitas, koefisien konsolidasi dan tanah lempung lunak lahan basah.One way to accelerate water flow and the rate of consolidation of wetland soft clay soil is by adding porous material in the soil and using vertical drainage. So far there has been a development of consolidation acceleration technology with a vertical drain made from geosynthetics. Apart from geosynthetics, other materials for vertical drain material are still being developed to find economical reliability. The problem in this research is how the degree of consolidation resulting from the consolidation test of wetland soft clay soil is added by the presence of porous material (made from sand, rice husk, and wood charcoal). In addition, also the effect of radial drainage (porous material), n (comparison of the diameter of the specimen and drainage diameter (porous material) of each porous material. In this study a consolidation test was carried out with specimens using soft soil wetlands. the center of the specimen was given a hole with a diameter of 0.75cm, 1cm, and 1.5cm, then added porous material made from fillers in the form of sand, rice husk, and charcoal. porous material) in the soil The results showed that rice husk, sand and charcoal material can be used as drainage material (porous material) for the soil that consolidates because it can increase the value of the consolidation degree (U%). for the type of drainage material (porous material) made from chaff can produce console degrees idasi which is bigger than drainage material (porous material) made from sand or charcoal. Drainage material (porous material) made from chaff can produce consolidated coefficient values (Cv), permeability coefficient value (k), and volume change coefficient value (mv) which is greater than the drainage material (porous material) made from sand and charcoal. The value of the consolidation coefficient (Cv) increases along with the increase in the diameter ratio (n) until it reaches the optimum diameter ratio (nopt), then after the optimum diameter ratio value is reached, the coefficient of consolidation will decrease. The optimum diameter ratio in soft clay that consolidates is obtained at a value of 6 (six). Keywords: Soil consolidation, vertical drainage (porous material), degree of consolidation, permeability coefficient, consolidation coefficient, and wetland soft clay soil.