Storage of potatoes

1978 ◽  
Vol 9 (5) ◽  
pp. 253-259 ◽  
Author(s):  
M Eddowes
Keyword(s):  
Frost Damage ◽  
Premium Price ◽  
Farm Buildings

Losses of potatoes during storage due to disease, softening of tubers, sprouting and frost damage frequently exceed 25%, particularly when they are stored in field clamps or unmodified farm buildings. Though the condition and health of the crop when stored is of overriding importance, the use of refrigeration and forced-draught ventilation can reduce such losses spectacularly. But the high cost of purpose-built stores requires a high premium price for late-marketed produce.

Influence of planting date and row covers on yields and crop values for bell peppers in Saskatchewan

1992 ◽  
Vol 72 (2) ◽  
pp. 527-533 ◽  
Author(s):  
D. R. Waterer
Keyword(s):  
Fruit Set ◽  
Frost Damage ◽  
Planting Date ◽  
Early Planting ◽  
Row Covers ◽  
Crop Development ◽  
Bell Peppers ◽  
Premium Price ◽  
Black Plastic ◽  
Crop Maturity

In 1989 and 1990, bell peppers transplanted into the field in mid-May, late May or early June were grown with a black plastic soil mulch and no cover (NC) or under tunnels of perforated clear polyethylene (PT) or spunbonded polyester (ST). The ST treatment provided several degrees of frost protection, whereas the PT treatment appeared to increase the crop’s susceptibility to frost damage. Early planting had little effect on total fruit yields but did accelerate the harvest. In both years, the ST accelerated crop maturity and increased total fruit yields relative to the noncovered treatment. At times the PT improved crop development and increased fruit yields, but in many cases it reduced fruit yields relative to the noncovered treatment. By promoting early fruit set and development, early planting under the spunbonded row covers significantly enhanced the value of the crop, as early peppers command a premium price in Saskatchewan. Cumulative crop values for the PT treatments were generally similar to or poorer than those for the noncovered control.Key words: Bell pepper, Capsicum annuum, planting date, row covers, frost

Vulnerability of sweet cherry cultivars to continuous periods of spring frosts in Plovdiv, Bulgaria

2020 ◽  
Vol 12 (4) ◽  
pp. 348-352
Author(s):  
S. Malchev ◽  
S. Savchovska
Keyword(s):  
Sweet Cherry ◽  
Weather Conditions ◽  
Frost Damage ◽  
Cold Weather ◽  
Bud Burst ◽  
Intermediate Group ◽  
Air Temperatures ◽  
Wide Range ◽  
Group Form ◽  
Sweet Cherry Cultivars

Abstract. The periods with continuous freezing air temperatures reported during the spring of 2020 (13 incidents) affected a wide range of local and introduced sweet cherry cultivars in the region of Plovdiv. They vary from -0.6°C on March 02 to -4.9°C on March 16-17. The duration of influence of the lowest temperatures is 6 and 12 hours between March 16 and 17. The inspection of fruit buds and flowers was conducted twice (on March 26 and April 08) at different phenological stages after continuous waves of cold weather conditions alternated with high temperatures. During the phenological phase ‘bud burst’ (tight cluster or BBCH 55) some of the flowers in the buds did not develop further making the damage hardly detectable. The most damaged are hybrid El.28-21 (95.00%), ‘Van’ (91.89%) and ‘Bing’ (89.41%) and from the next group ‘Lapins’ (85.98%) and ‘Rosita’ (83.33%). A larger intermediate group form ‘Kossara’ (81.67%), ‘Rozalina’ (76.00%), ‘Sunburst’ (75.00%), ‘Bigarreau Burlat’ (69.11%) and ‘Kuklenska belitza’ (66.67%). Candidate-cultivar El.17-90 ‘Asparuh’ has the lowest frost damage values of 55.00% and El.17-37 ‘Tzvetina’ with damage of 50.60%.

Interaction Between CPPU and NAA on Fruit Thinning and Fruit Development in Selected Apple Cultivars

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 513c-513 ◽  
Author(s):  
Martin J. Bukovac ◽  
Jerome Hull ◽  
John C. Neilsen ◽  
Michael Schroeder ◽  
Georg Noga
Keyword(s):  
Total Yield ◽  
Fruit Size ◽  
Frost Damage ◽  
Fruit Growth ◽  
Soluble Solids ◽  
Seed Number ◽  
Crop Load ◽  
Fruit Thinning ◽  
Carpel Development ◽  
Return Bloom

NAA is used extensively for fruit thinning of apples to increase fruit size and to promote return bloom. In some cultivars, even if thinning is achieved, fruit size at harvest may be less than expected based on crop load. CPPU, N-(2-chloro-4-pyridinyl)-N.-phenylurea, has been shown to increase fruit growth in apples, grapes, and kiwi. We evaluated combinations of NAA and CPPU on thinning, fruit growth and return bloom in Redchief `Delicious', `Elstar', and `Gloster'. CPPU was applied at 5 mgμL–1 (based on 0 to 10 mgμL–1 response curve) in combination with 15 mgμL–1 NAA as high-volume sprays at 7 to 10 mm KFD. Yield and fruit size distribution (on total yield) were used as index of response. In `Delicious', CPPU (3-year study) increased % large (70 mm+) fruit, but in the presence of NAA % large fruit was reduced 2 of the 3 years. CPPU did not induce significant thinning. There were no significant effects on color or soluble solids; firmness was increased slightly and seed number reduced. The L/D ratio was increased and uneven lobe and carpel development was common. CPPU had no significant effect on return bloom in presence or absence of NAA, but NAA increased bloom in both the presence and absence of CPPU. With `Elstar' (2-year study) there was no significant thinning with either chemical, but CPPU increased mean fruit size and % large (70–80 mm) fruit over nonthinned, but not significantly greater than NAA alone. There were no significant differences in firmness, color, soluble solids or seed number. NAA + CPPU did not inhibit fruit growth or cause excessive uneven carpel development. Frost damage reduced crop load in `Gloster' where results were similar to `Elstar' except seed number was reduced by the NAA + CPPU combination.

Do Sellers with Expected Losses Obtain a Premium Price? Really?

2020 ◽  
Author(s):  
Tingyu Zhou ◽  
John M. Clapp ◽  
Ran Lu-Andrews
Keyword(s):  
Premium Price

Climate-induced treeline mortality during the termination of the Little Ice Age in the Greater Yellowstone Ecoregion, USA

The Holocene ◽  
2021 ◽  
pp. 095968362110116
Author(s):  
Maegen L Rochner ◽  
Karen J Heeter ◽  
Grant L Harley ◽  
Matthew F Bekker ◽  
Sally P Horn
Keyword(s):  
Climate Change ◽  
Tree Ring ◽  
Little Ice Age ◽  
Climate Changes ◽  
Frost Damage ◽  
Ice Age ◽  
Spatial And Temporal Variability ◽  
Whitebark Pine ◽  
Engelmann Spruce ◽  
Greater Yellowstone

Paleoclimate reconstructions for the western US show spatial variability in the timing, duration, and magnitude of climate changes within the Medieval Climate Anomaly (MCA, ca. 900–1350 CE) and Little Ice Age (LIA, ca. 1350–1850 CE), indicating that additional data are needed to more completely characterize late-Holocene climate change in the region. Here, we use dendrochronology to investigate how climate changes during the MCA and LIA affected a treeline, whitebark pine ( Pinus albicaulis Engelm.) ecosystem in the Greater Yellowstone Ecoregion (GYE). We present two new millennial-length tree-ring chronologies and multiple lines of tree-ring evidence from living and remnant whitebark pine and Engelmann spruce ( Picea engelmannii Parry ex. Engelm.) trees, including patterns of establishment and mortality; changes in tree growth; frost rings; and blue-intensity-based, reconstructed summer temperatures, to highlight the terminus of the LIA as one of the coldest periods of the last millennium for the GYE. Patterns of tree establishment and mortality indicate conditions favorable to recruitment during the latter half of the MCA and climate-induced mortality of trees during the middle-to-late LIA. These patterns correspond with decreased growth, frost damage, and reconstructed cooler temperature anomalies for the 1800–1850 CE period. Results provide important insight into how past climate change affected important GYE ecosystems and highlight the value of using multiple lines of proxy evidence, along with climate reconstructions of high spatial resolution, to better describe spatial and temporal variability in MCA and LIA climate and the ecological influence of climate change.

scholarly journals Effect of a Nitrite/Nitrate-Based Accelerator on the Strength Development and Hydrate Formation in Cold-Weather Cementitious Materials

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1006
Author(s):  
Akira Yoneyama ◽  
Heesup Choi ◽  
Masumi Inoue ◽  
Jihoon Kim ◽  
Myungkwan Lim ◽  
...  
Keyword(s):  
Calcium Nitrate ◽  
Hydrate Formation ◽  
Frost Damage ◽  
Cementitious Materials ◽  
Heat Of Hydration ◽  
Cold Weather ◽  
Strength Development ◽  
Hardened Cement ◽  
Tricalcium Aluminate ◽  
Nitrite Nitrate

Recently, there has been increased use of calcium-nitrite and calcium-nitrate as the main components of chloride- and alkali-free anti-freezing agents to promote concrete hydration in cold weather concreting. As the amount of nitrite/nitrate-based accelerators increases, the hydration of tricalcium aluminate (C3A phase) and tricalcium silicate (C3S phase) in cement is accelerated, thereby improving the early strength of cement and effectively preventing initial frost damage. Nitrite/nitrate-based accelerators are used in larger amounts than usual in low temperature areas below −10 °C. However, the correlation between the hydration process and strength development in concrete containing considerable nitrite/nitrate-based accelerators remains to be clearly identified. In this study, the hydrate composition (via X-ray diffraction and nuclear magnetic resonance), pore structures (via mercury intrusion porosimetry), and crystal form (via scanning electron microscopy) were determined, and investigations were performed to elucidate the effect of nitrite/nitrate-based accelerators on the initial strength development and hydrate formation of cement. Nitrite/nitrate-AFm (aluminate-ferret-monosulfate; AFm) was produced in addition to ettringite at the initial stage of hydration of cement by adding a nitrite/nitrate-based accelerator. The amount of the hydrates was attributed to an increase in the absolute amounts of NO2− and NO3− ions reacting with Al2O3 in the tricalcium aluminate (C3A phase). Further, by effectively filling the pores, it greatly contributed to the enhancement of the strength of the hardened cement product, and the degree of the contribution tended to increase with the amount of addition. On the other hand, in addition to the occurrence of cracks due to the release of a large amount of heat of hydration, the amount of expansion and contraction may increase, and it is considered necessary to adjust the amount used for each concrete work.

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