Int. J. Plant Biol., Volume 7, Issue 1 (July 2016) – 14 articles

The aim of this research was to describe the potency of superior cultivar upland rice candidates (gogo rice) first generation (M1) which generated from Pae Pulu Pongasi and Pae Loilo, Southeast Sulawesi, Indonesia. The grains were irradiated by 60 Co gamma-rays at 100, 200, 300, and 400 Gy doses. The developed cultivar was selected from numerous red and black rice with highest anthocyanins. Based on LD50 test to these cultivars, Pae Pulu Pongasi cultivar was founded at 416 Gy and Pae Loilo about 360 Gy. Ten superior lines candidates were selected, namely M1.27K2D1, M1.190K2D3 which are derived from M1 Pae Pulu Pongasi cultivar and M1.6K3D1, M1.24K3D1, M1.37K3D1, M1.102K3D1, M1.104K3D1, M1.162K3D1, M1.170K3D1 which derived from M1 Pae Loilo cultivars. M1.81K2D1 derived from M1 Pae Pulu Pongasi had the potential to produce higher yield, high lodging resistance, and short harvest age compared to parental. Full article

Curvularia lunata was isolated from leaf spot of rice var. Sen Pidoa and tested for pathogenicity. Chaetomium cupreum CC3003 expressed antifungal activity against C. lunata in dual culture test. Hexane-crude extract, EtOAc-crude extract and methanol-crude extract from C. cupreum inhibited sporulation of C. lunata with ED50 of 6.41, 0.83 and 7.81 μg/mL, respectively. Pot experiment revealed that plant heights in treated with a spore suspension of C. cupreum, bioformulation of C. cupreum, nano product from C. cupreum and tebuconazole were not significantly different when compared to the inoculated control. Disease reduction compared to the inoculated control from treatment with a spore suspension of Chaetomium, bioformulation of C. cupreum, nano product from C. cupreum and tebuconazole ranged between 41.66% to 58.33%. Field experiment indicated that chemical method was decreased leaf spots infection by 60%, followed by organic method (40%) and GAP methods (40%) , respectively. The chemical and GAP methods were significantly higher in grain weight than the organic method when compared to the non-treated control. This is the first report using C. cupreum to control leaf spot of rice var. Sen Pidoa caused by C. lunata in Cambodia. Full article

The potential of seed priming by different chemicals on alleviation of growth inhibition of rice (Oryza sativa L.) seedlings under salt stress was investigated. A preliminary experiment using 10 seed-priming chemicals including NaCl, KCl, CaCl₂, KNO₃, ascorbic acid (AsA), mannitol, polyethylene glycol (PEG6000), sorbitol, wood vinegar and distilled water revealed that mannitol, KNO₃ and wood vinegar were more effective than the others in alleviating salt-induced growth inhibition of 10- day-old seedlings. Various concentrations of mannitol (1, 2 and 3%), KNO₃ (0.25, 0.5 and 0.75%) and wood vinegar (1:1000, 1:300 and 1:100 dilutions) were subsequently used to prime rice seeds to investigate the effects on mitigation of salt-induced growth inhibition and modulation of physiological responses of 4-week-old rice plants grown in a hydroponic solution. All tested concentrations of mannitol, KNO₃ and wood vinegar resulted in seedlings with significantly higher dry weights than those grown from non-primed and hydroprimed seeds under both controlled and saltstressed (150 mM NaCl, 7 days) conditions. Under salt stress, enhanced growth of seedlings raised from seeds primed with all three chemicals was attributable to greater membrane stability, higher chlorophyll content and lower Na⁺/K⁺ ratio. Full article

Accession of red rice does not have the traits of early maturity, drought tolerance and high yield. Mutation is needed to obtain the desired genetic resources. Gamma-ray irradiation is the right method because it was proved capable of producing hundreds of new varieties, which are better than the previous. This study aimed to identify the improvement of early maturity and drought tolerance of red rice mutant to gamma ray irradiation results. The research materials are M4, M5 and M6 strain, which are derived from the Bangka’s accession local red rice (Celak Madu, Ruten Puren and radix). The three accession seed have been treated with gamma-ray irradiation doses of 150, 200 and 250 Gray. The results showed gamma ray irradiation dose of 150 Gray and 200 Gray to red rice accession can form a mutant with the character of harvesting time less than 115 days after planting and was more drought tolerant than the previous. M6-GR150- 1-9-13 strain was selected as a candidate for early maturity, drought tolerant and high yield mutant. Full article

The effects of three commercial substrates (a mixture of forest residues, composted grape husks, and white peat, black peat and coir) on plant growth and nitrogen (N) and nitrate (NO₃) concentration and content were evaluated in spinach (Spinacia oleracea L. cv. Tapir). Spinach seedlings were transplanted at 45 days after emergence into Styrofoam boxes filled with the substrates and were grown during winter and early spring in an unheated greenhouse with no supplemental lighting. Each planting box was irrigated daily by drip and fertilized with a complete nutrient solution. The NO₃ content of the drainage water was lower in coir than in the other substrates. However, shoot NO₃ concentration was not affected by substrate type, while yield and total shoot N and NO₃ content were greater when plants were grown in peat than in the mixed substrate or the coir. Leaf chlorophyll meter readings provided a good indication of the amount of N in the plants and increased linearly with total shoot N. Full article

Growth and physical quality of Paraserianthes falcataria (L.) Nielsen seedling is determined by the quality and quantity of transplanting media. The aim of this research is to determine the best transplanting media for growing P. falcataria seedling. Research started with sowing P. falcataria seed in plastic container until the seedling grow. After 2 weeks of age, seedling was placed in ten types of transplanting media. Transplanting media consist of Sidoarjo’s mud soil, rice husk, compost and cow manure. Each types of transplanting media were made from different concentration of mud, rice husk, compost and cow manure. Result showed that the highest growth of P. falcataria seedling was found in M4 with 31.0 cm. However, this result was not significantly different with M1 which the high is 30.6 cm. Other P. falcataria seedlings showed varied growth with the value ranging from 27.6 to 29.9 cm. M4 also showed highest stem diameter, root length and leaves number with value 0.50 cm; 20.6 cm; 50.1 respectively. Root dry weight and stem+leaf dry weight were also highest on M4 with value 1.4 g and 4.9 g. RRSL and Seed Quality Index were also highest on M4 with value 3.50 and 0.09. It was concluded that M4 is the best transplanting media for P. falcataria seedling. Full article

In this work we conducted a quantitative analysis of the nuclear DNA-content of developing sperm cells of the plant Brassica campestris L. The sperm cells were in young pollen grain, mature pollen grain and pollen tubes. When generative cells, at the pre-anthesis stage, split into two sperm cells, we have established that the newly-formed sperm cells begin to synthesize nuclear DNA in developing pollen grain of B. campestris. We measured this DNA-content during the development of sperm cells. The results indicate that during development, sperm cells of B. campestris have passed the G₁ phase of the cell cycle and entered the S phase, presumably then fusing with egg cells at a level of 2C, as is characteristic of G₂ type fertilization in angiosperms. Full article

Twenty-four accessions of twelve species minor legumes collected from the germplasm unit of the International Institute of Tropical Agriculture Ibadan, Nigeria were evaluated for their genetic diversities and phylogenetic relatedness. The accessions were planted into plots of 5 ridges of 5 meters long, spaced 1 meter apart and replicated three times at the Federal University Oye-Ekiti Teaching and Research Farm. The diversity and the relative phylogeny of the accessions were assessed through their floral morphological differences and the mean values between two accessions were evaluated by descriptive statistics. Principal component analysis was employed to identify the most discriminatory floral morphological traits and the similarities among the 24 accessions were assessed by cluster analysis (CA). Descriptive statistics through Duncan multiple range test adopted revealed genetic diversity and phylogenetic relatedness among the accessions. The first two principal component axes explained 64.66% of the total floral morphological variation. Standard petal length, calyx lobe length and stipule length contributed most of the variations in the legume accession. CA grouped the 24 accessions into six clusters. The study revealed intra-specific similarities and inter-specific floral morphological differences among the studied accessions. Full article

A fragment of 772 bp of the chloroplast maturase K gene was amplified and sequenced for Rosa x damascena trigintipetala variety growing in Taif region of Saudi Arabia. The data were aligned with their counterparts of other varieties already found in the Genbank database and were analyzed by maximum-parsimony, neighbor-joining and maximum-likelihood methods and a single rooted tree was executed. R. x damascena trigintipetala was paraphyletic where one sample [A] clustered with all varieties while the second [B] was basal. R. x damascena was sister to R. x chinensis semperflorens with the later being basal. R. x damascena gori was basal for all taxa studied. R. moschata was inside the clade of R. x damascena. Hybridization could be possible among R. damascena, R. chinensis and R. moschata. The genetic distance and tree topology indicated that [A] variety could be originated from R. moshata while [B] could be originated from gori or R. chinensis semperflorens. We, therefore, may consider that R. x damascena gori or R. chinensis could be the origin of all nowadays R. x damascena varieties. Full article

Araçà-boi is a fruit, which awakes great interest for presenting pulp of quality. Their seeds are recalcitrant and present a relatively short period of viability. The water absorption by seeds is a mechanism of growth resuming of the embryo with a subsequent of the tegument breakage by the radical. The seed electric conductivity is a vigor testing is directly related to the membrane permeability. Study of the curve of water absorption by the araçá-boi seeds will contribute to characterize their germination process. In this context, studies concerned with seeds were conducted, which characterized the mass, biometrics, water content, electric conductivity and water imbibition by seeds. It was found that the population of plants established in Manaus-AM produces small, medium and large seeds and which present 70.2, 68.2 and 47.5% of moisture. The greatest water increase takes place in the first hour of absorption, regardless of the size of seeds and water absorption velocity is not influenced by their size. The imbibition curves characterized in the 144-hour period, independent of the size of seeds, show changes of two physiological phases. Both the large and medium seeds present smaller conductivity values, obtaining smaller percentages of germination for possessing increased vigor indices. Full article

The increasing interest in Arundo donax, a perennial lignocellulosic species only reproducing by propagation, requires the setup of cheap, simple and reliable techniques. Considering these targets, stem cutting offers considerable advantages. The present investigation aimed to compare: (i) plants obtained by different propagation methods (by rhizome and micropropagation mother plants); (ii) plants obtained by stem cuttings from basal, central and apical parts of the stem; (iii) different planting periods (spring, summer, autumn). The obtained results showed that the number of new shoots from stem buds was: (i) higher in the spring and lower in the summer planting period; (ii) higher from cuttings obtained by micropropagated than rhizome mother plants, both in spring and summer plantings; (iii) decreasing passing from the basal to the apical stem portion; (iv) partly unexpressed in the autumn planting period; (v) lower from one-year stem cuttings as compared to two-year stem cuttings. Full article

Artificial light, supplied by fluorescent lamps, has been effectively utilized in controlled- environment chambers for horticulture and floriculture nursery. This experiment aimed at investigating whether light-emitting diodes (LEDs) have the same effectiveness on plant morphology, photosynthetic and physiological responses as FLUORA lamps. Seedlings of common dandelion (Taraxacum officinale) and purple coneflower (Echinacea purpurea), species of high interest for their nutraceutical properties, were grown in controlled-environment chambers for 50 days under LED and FLUORA light sources as sole-source lighting systems, and the effects of artificial light supplies on plant photosynthetic performance and chlorophyll content (SPAD) were evaluated. The results were compared to plants grown under natural sunlight. In both species, total chlorophyll content (SPAD) values decreased for plants under sunlight, and for those grown under FLUORA lighting throughout the experimental period, while the values measured for plants grown under LEDs maintained a relatively constant value. At the end of the experiment, plant dry matter in both species was significantly lower under LEDs and FLUORA lighting, than the plants exposed to solar light. The two species showed different gas exchange dynamics under LEDs and FLUORA lighting, and photosynthetic performance decreasing after 10 days of light treatment compared to plants under sunlight. The results demonstrated that for common dandelion and purple coneflower photosynthetic processes are often modified when the species are cultivated under these artificial lighting and in controlled- environment chambers, because lamps do not able to generate the same spectrum and energy of sunlight. Full article

Pulasan (Nephelium ramboutan-ake) is a species of Sapindaceae which has hermaphrodite and staminate flowers on different trees. Morphological flower structures and pollination types of the pulasan fruit tree have not previously been reported thoroughly. This study was undertaken to observe the reproductive structure of flowers, and to examine its correlation with pulasan pollination type. A total of 67 hermaphrodite and 14 male trees of pulasan were observed. Some hermaphrodite inflorescences were covered using cloth bags for between four and six weeks to calculate number of fruit, and to determine their pollination system. The number of individual flowers per inflorescence on male pulasan trees was higher than for hermaphrodite ones. Panicles and spikes were found on both types of pulasan inflorescence. Flowers having four sepals was the commonest structure in both flower types. However, five stamens were commonly found in hermaphrodite flowers, while male flowers often had six. In general, stigma were curved in shape, with modification in some flowers. Anther of hermaphrodite pulasan flowers naturally never open, although their pollen is viable, so there is a mechanical barrier for self-pollination. It was concluded that pulasan tends to be an allogamous plant. Full article

The most enigmatic feature of mature thylakoids of Angiosperms is the presence of piles of membranous discs forming the cylindrical structures known as grana. Although some models aim to elucidate their formation, until now the mechanism governing the architecture of thylakoid stacks remains obscure. In this work a new model is presented aiming to explain the way thylakoids stack. In comparison with previous models, this model proposes a dynamic mechanism for the rapid selfassembly of thylakoid stacks and their subsequent disassembly under the influence of a variety of physicochemical factors and is consistent with the evolutionary origin of these membranes and their ontogenetic continuity. The model proposes that, under the influence of attractive electrostatic forces, the membranes come closer in a parallel alignment and the photosystem II/light harvesting complexes migrate laterally forming circular aggregates. Finally the thylakoids rotate around the vertical axis of the superimposed aggregates, under the action of a torque. Full article