Photosynthesis, Resource Acquisition and Growth Responses of Two Biomass Crops Subjected to Water Stress
Elena Sánchez,
Gladys Lino,
Claudia Arias,
Xavier Serrat,
Salvador Nogués
Issue:
Volume 6, Issue 3, June 2018
Pages:
68-86
Received:
2 May 2018
Accepted:
19 May 2018
Published:
25 June 2018
DOI:
10.11648/j.jps.20180603.11
Downloads:
Views:
Abstract: This study compares photosynthesis, growth, 13C and 15N labelling patterns of two biomass crops (Arundo donax L. and Panicum virgatum L.) grown under water stress in greenhouse conditions. Plants were exposed to three water stress levels: control (C, 100% Pot Capacity), mild stress (MS, 50% PC) and severe stress (SS, 25% PC). Photosynthesis, fluorescence parameters and relative water content were measured at the beginning (Ti) and the end of the experiment (Tf). Biomass parameters were measured at Tf. Short-term double labelling with 13C and 15N stable isotopes was performed in both species. Isotopic analyses of total organic matter, total soluble sugars and the CO2 respired were undertaken at T0 (pre-labelling), T1 (24h after labelling) and T2 (7 days after labelling). Immediately after the 13C and 15N labelling, stems and rhizomes seemed to be the main sinks for labelled carbon and nitrogen in both species. Moreover, not all of the labelled carbon and nitrogen substrate was used by plant metabolism after seven days. Decreases in photosynthesis parameters were observed as a consequence of the increase in water stress (WS) in both species, with a greater magnitude decline in giant reed than in switchgrass. A decrease in height, number of green leaves and total dry weight due to WS was observed in both species. Both species were more 13C-enriched and more 15N-depleted during the increases in WS due to lower stomatal conductance and transpiration. In general, WS accelerated plant phenology and, consequently, the accumulation of storage compounds in the rhizome occurred in response to stress. This effect was more clearly visible in switchgrass than in giant reed.
Abstract: This study compares photosynthesis, growth, 13C and 15N labelling patterns of two biomass crops (Arundo donax L. and Panicum virgatum L.) grown under water stress in greenhouse conditions. Plants were exposed to three water stress levels: control (C, 100% Pot Capacity), mild stress (MS, 50% PC) and severe stress (SS, 25% PC). Photosynthesis, fluore...
Show More
Research Progress of Leaf Senescence Related Genes in Tobacco
Xiaoming Gao,
Yongfeng Guo
Issue:
Volume 6, Issue 3, June 2018
Pages:
87-92
Received:
7 May 2018
Accepted:
7 July 2018
Published:
31 July 2018
DOI:
10.11648/j.jps.20180603.12
Downloads:
Views:
Abstract: Tobacco (Nicotiana tabacum L.) is an important model plant that has been widely used in plant biological research. Tobacco is also an economic crop in which mature yellow leaves are harvested. Leaf maturity and the yellowing process have a decisive influence on the quality of tobacco products. The mechanism, influencing factors and regulating genes of plant leaf senescence was briefly summarized in this review.The research progress in genes related to tobacco leaf senescence and the effects of exogenous genes on the senescence of tobacco was also summarized. It is of great importance to study tobacco leaf senescence process and related genes in order to improve the quality of tobacco.
Abstract: Tobacco (Nicotiana tabacum L.) is an important model plant that has been widely used in plant biological research. Tobacco is also an economic crop in which mature yellow leaves are harvested. Leaf maturity and the yellowing process have a decisive influence on the quality of tobacco products. The mechanism, influencing factors and regulating genes...
Show More
The Use of Encapsulation-Dehydration Technique for Short-Term Preservation of Endangered Sweet Potato Landraces (Ipomoea batatas Lam) from Benin
Arsène Mahoutondji Doussoh,
Justine Sossou Dangou,
Arnaud Agbidinoukoun,
Serge Sètondji Houedjissin,
Corneille Ahanhanzo
Issue:
Volume 6, Issue 3, June 2018
Pages:
93-100
Received:
25 June 2018
Accepted:
11 July 2018
Published:
6 August 2018
DOI:
10.11648/j.jps.20180603.13
Downloads:
Views:
Abstract: Ex situ conservation of genetic resources remains a challenge for preservation of vegetatively propagated species such as sweet potato. The objective of this study was to establish the protocol based on the encapsulation-dehydration technique for short term preservation of endangered sweet potato landraces produced in Benin. Thus, the evaporative dehydration duration on silicagel was previously determinated on the empty beads which were made using alginate sodium (3%) and calcium chloride (1.32M). Then, the young shoots of two sweet potato landraces (Koïdokpon and Dokoui carotte) growing in the screen house were cutted aseptically and desinfected with 10% sodium hypochlorite. The apices were excised on stereoscope and were encapsulated prior their dehydration on silicagel during 5 and 6h. The encapsulated apices were finally conserved in eppendorf tubes at 2°C in batches for 15 days and 90 days. The encapsulated apices were cultured in MS medium supplemented with 0.15 mg/l BAP, 0.2 mg/l NAA, 0.08 mg/l GA3 and 80 mg/l adenine sulfate. The survival and the regeneration rates were then evaluated. At our experimentation condition, the dehydration duration which allowed around 20% water content of the beads was 6h. For the encapsulated apices, the highest survival rates (59.26% and 37.04%) and the highest regeneration rate (37.04% and 11.11%) were recorded respectivelly with the landraces ''Koïdokpon'' and ''Dokoui carotte'' when the apices were dehydrated by 6h and stored for 15 days. The regeneration rates decreased according to the stored duration. Significant difference was noted on the regeneration of apices for the landraces tested. This method can be used to preserve the endangered sweet potato landraces and other species during at least three months without subcultures. It also reduce the cost of conservation in terms of consumables and permit better genotype stability during the storage.
Abstract: Ex situ conservation of genetic resources remains a challenge for preservation of vegetatively propagated species such as sweet potato. The objective of this study was to establish the protocol based on the encapsulation-dehydration technique for short term preservation of endangered sweet potato landraces produced in Benin. Thus, the evaporative d...
Show More
Genotype x Environment Interaction and Stability Analysis for Gran Yield of Diallel Cross Maize Hybrids Across Tropical Medium and Highland Ecologies
Alphonse Nyombayire,
John Derera,
Julia Sibiya,
Claver Ngaboyisonga
Issue:
Volume 6, Issue 3, June 2018
Pages:
101-106
Received:
5 April 2018
Accepted:
23 April 2018
Published:
21 August 2018
DOI:
10.11648/j.jps.20180603.14
Downloads:
Views:
Abstract: Genotype x environment (G x E) interaction is the differential performance of genotypes across environments, especially in the tropics where seasonal and spatial variability is large. This results in serious challenges of product selection across environments. The objectives of this study were to determine G x E interaction and yield stability of new diallel cross maize hybrids and to identify suitable genotypes for the medium and highland ecologies in Rwanda. Forty- five diallel cross maize hybrids and three commercial checks were evaluated in four locations representing the major agro-ecologies of Rwanda over three seasons. The data were subjected to genotype and genotype by environment interaction (GGE) biplot analysis, using Genstat statistical package. The analysis revealed two mega-environments which discriminated the hybrids. Two genotypes 3 (S1/S4) and 25 (S4/S5) displayed specific adaptation; qualifying them as candidates for further testing in respective mega-environments. Genotypes 3 (S1/S4) and 29 (S4/S9) demonstrated high yield and stability. Overall, the study revealed crossover interaction and there is need to breed for both broad and specific adaptation in these medium and high altitude environments.
Abstract: Genotype x environment (G x E) interaction is the differential performance of genotypes across environments, especially in the tropics where seasonal and spatial variability is large. This results in serious challenges of product selection across environments. The objectives of this study were to determine G x E interaction and yield stability of n...
Show More
