Experiments were conducted in 1997, 1998 and 1999 to determine the effects of mulch/mini-tunnel and thermal-water tube combinations on daily carbon dioxide (CO2) concentration, air, soil temperatures and early growth of muskmelons (var. Earligold) during the vegetative phase. Treatments consisted of mulched plot covered with a clear perforated, a clear non-perforated or a non-perforated infrared polyethylene mini-tunnel with the absence or the presence of a thermal-water tube compared with control treatments. Additional treatments consisting of the ventilation non-perforated clear and infrared tunnels containing no tube were used in 1998 and 1999. The non-perforated tunnels significantly increased CO2 concentrations, air and soil temperatures compared with those of perforated tunnels and controls. Inclusion of a thermal-water tube reduced air temperature fluctuations in the tunnels. Ventilating the non-perforated tunnels significantly decreased CO2 concentrations and air temperatures. / During the first 10--15 days after transplanting, muskmelons grown in the non-perforated tunnels had higher relative growth rate (RGR), net assimilation rate (NAR), and dry weight than those of grown under perforated tunnels and in the control plots. However, during the later period, 11--16 days after transplanting to anthesis, the effects of mulch/mini-tunnels on the RGR, NAR and dry weight of muskmelons were inconsistent. Muskmelons grown in the mulch/tunnels had significantly higher RGR, but generally lower NAR, than those of grown without tunnel. The use of mulch/mini-tunnels significantly increased dry weight at anthesis in 1997, but not in 1998 and 1999. The presence of thermal-water tube in the tunnels and ventilating the non-perforated tunnels generally increased RGR, NAR, and dry weight of muskmelons. The use of mulch/mini-tunnels reduced time for muskmelon to reach anthesis by 9 to 11 days. / The leaves of muskmelons grown in mulch/mini-tunnels had significantly lower ratios of variable to maximum fluorescence (Fv/Fm) than control plants throughout the experiments, except at 10 and 20 days after transplanting in 1997. Leaves of muskmelons grown in non-perforated tunnels had significantly higher levels of chlorophyll than all other treatments during first 15 days after transplanting. However, chlorophyll values in these treatments decreased as muskmelons reached anthesis. The presence of a thermal-water tube in the mulch/mini-tunnels and ventilating the non-perforated tunnels generally increased both Fv/Fm ratios and chlorophyll levels of muskmelon leaves.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.35565 |
| Date | January 2000 |
| Creators | Aziz, Fahrurrozi. |
| Contributors | Stewart, K. A. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Plant Science.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001762080, proquestno: NQ64504, Theses scanned by UMI/ProQuest. |
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