Search Results

You are looking at 1 - 2 of 2 items for

  • Author or Editor: Muhammad Imran Al-Haq x
  • Refine by Access: All x
Clear All Modify Search
Free access

Muhammad Imran Al-Haq, Y. Seo, S. Oshita, and Y. Kawagoe

The fungicidal effectiveness of electrolyzed oxidizing (EO) water on peach [Prunus persica (L.) Batsch.] fruit was studied. Fruit were inoculated with a spore suspension of 5 × 105 conidia/mL of Monilinia fructicola [(G. Wint.) Honey] applied as a drop on wounded and nonwounded fruits, or by a uniform spray-mist on nonwounded fruits. Fruit were immersed in tap water at 26 °C for 5 or 10 minutes (control), or treated with EO water varying in oxidation-reduction potential (ORP), pH, and free available chlorine (FAC). Following treatment, fruit were held at 20 °C and 95% relative humidity for 10 days to simulate retail conditions. Disease incidence was determined as the percentage of fruits showing symptoms of the disease, while severity was expressed as lesion diameter. EO water did not control brown rot in wound-inoculated fruits, but reduced disease incidence and severity in nonwound-inoculated peach. Symptoms of brown rot were further delayed in fruit inoculated by a uniform-spray mist compared with the nonwounded-drop-inoculated peaches. Fruit treated with EO water held for 8 days at 2 °C, 50% RH, did not develop brown rot, until they were transferred to 20 °C, 95% RH. The lowest disease incidence and severity occurred in fruit immersed in EO water for up to 5 minutes. EO water having pH 4.0, ORP 1,100 mV, FAC 290 mg·L-1 delayed the onset of brown rot to 7 days, i.e., about the period peach stays in the market from a packing house to consumer. No chlorine-induced phytotoxicity was observed on the treated fruit. This study revealed that EO water is an effective surface sanitizer, but only delayed disease development.

Free access

Muhammad Imran Al-Haq, Junichi Sugiyama, Akiko Tomizawa, and Yasuyuki Sagara

The effect of amount of manure (animal dung) on the texture of muskmelons (Cucumis melo L.) has been studied. Melons were grown in a greenhouse with 20 and 50 t·ha-1 of manure. Melons were harvested four times at 4-day intervals and kept at ambient conditions for about 8-12 days. Texture was determined by using “Firm Tester” that employs acoustic technology and to provide a firmness index expressed as transmission velocity [meters per second (m/s)]. At the time of the first, second, third and fourth harvest the fruit grown with 20 t·ha-1 manure gave mean transmission velocities of 54.5 ± 2.5, 55.2 ± 5.7, 49.6 ± 4.8, and 46.8 ± 9.4 m/s, respectively. Linear regression equations for fruit grown with 20 t·ha-1 manure showed that the fruit from the first harvest took 10 days to reach 40 m/s, while fruit from the second, third and fourth harvest took 11, 9.5, and 4 days, respectively, to reach this index. The corresponding values for fruit grown in 50 t·ha-1 of manure were 7.5, 10, 5.5 and 4.5 days, those from the second harvest gave the best keeping quality. The firmness index of melon grown in 20 t·ha-1 of manure was greater than that grown in 50 t·ha-1 manure. Higher soil NO3-N contents were associated with softer melons. The correlation between panelist scores for texture and the firmness index was 0.907. Both °Brix and panelist scores for sweetness indicated that manure did not affect the sweetness of melon. The digital firmness tester could detect the effect of manure on the texture of the melons, and could be used to determine the appropriate time of harvest for each and every individual melon.