Screening of kenaf (Hibiscus cannabinus L.) genotypes for low temperature requirements during germination and evaluation of feasibility of seed production in Italy |
| |
| Institution: | 1. Plant Sciences Technician, USDA-ARS, Northwest Watershed Research Center, Boise, ID 83702, USA;2. Plant Physiologist, USDA-ARS, Northwest Watershed Research Center, Boise, ID 83702, USA;3. Professor, Department of Geosciences, Boise State University, Boise, ID 83725, USA;4. Geneticist, USDA-ARS National Laboratory for Genetic Resources Preservation, Fort Collins, CO 80521, USA;5. Rangeland Management Specialist, USDA-ARS, Rangeland and Pasture Research Unit, Woodward, OK 73801, USA;6. Research Hydraulic Engineer, USDA-ARS, Northwest Watershed Research Center, Boise, ID 83702, USA;1. Department of Earth and Environmental Sciences, University of Pavia, Via S. Epifanio 14, 27100 Pavia, Italy;2. DAFNAE Department, University of Padova, Viale dell''Università 16, 35020 Legnaro (PD), Italy;3. Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126 Bologna, Italy |
| |
| Abstract: | Kenaf (Hibiscus cannabinus L.), an annual plant of the family Malvaceae, with potential use as a non-wood fiber source is a relatively new crop in Italy where it can be used in the manufacture of paper and pulp products. Cultivars differ markedly in their response to daylength, but stem growth generally declines rapidly following the onset of flowering such that under Italian conditions sowing for fiber production has to be carried out early to allow maximum growth before floral initiation. Sowing is generally delayed until soil temperature exceeds 12°C (approximately the middle of May), and therefore it is important to evaluate genetic diversity in response to low temperature during the germination stage to determine which kenaf cultivars are suited to early sowing. These trials screened various lines to identify those able to germinate at low temperature and therefore suitable for early sowing. The lines were also grown to evaluate photoperiodic requirements and seed yield in the trial environment (Experimental Centre of Rottaia, Pisa, central Italy, 43°40′N latitude;10°19′E longitude). In addition, the germination characteristics of seed obtained here were tested at low constant temperature (8°C) and at alternating 20–30°C temperature. Seed belonging to 15 lines – produced in Australia and selected for tolerance to low temperature – showed high germination percentage at 8°C in comparison with Tainung 2, a cultivar sensitive to low temperature and produced in USA (75 and 12% as overall mean of lines and Tainung 2, respectively). Lines differed significantly in their response to temperature both in germination percentage and mean germination time. Lines showed a wide range of duration of vegetative period. Flowering took place from 31 July to 23 August in most lines, and they are therefore considered early-maturing-types. Lines differed in duration of the period from emergence to seed maturity (from 134 to 187 days), in seed yield per plant (from 0.9 to 27.7 g plant−1), and harvest index (from 0.3 to 16.6%). In some lines, flowering occurred in mid-August and seed filling was then not completed due to low air temperature and unfavourable moisture conditions. Seed produced in central Italy had low quality due to more rapid deterioration and susceptibility to fungal pathogens. Sensitivity to low temperature during germination was greater in most lines and germination percentages were considerably lower than for seed produced in north-eastern Australia. Environmental conditions in central Italy appear inadequate for seed production. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
