Effect of root-zone and air temperature on flowering, growth and keeping quality of Begonia × hiemalis ‘Toran’

1990 ◽  
Vol 44 (1-2) ◽  
pp. 135-147 ◽  
Author(s):  
J.V.M. Vogelezang
HortScience ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 274G-274
Author(s):  
Jesse R. Quarrels ◽  
Steven E. Newman

Greenhouse studies of cut flower snapdragons (Antirrhinum majus L.) using two night air and two root-zone temperatures were conducted to determine the effects on growth and quality of four cultivars in two response groups [`Cheyenne' and `Rainier White' (group II) and `Tampico' and `Potomac' (group III)]. The group II cultivars were the earliest to harvest, but at the expense of quality. Grades of first, extra, and fancy only were harvested. Group III cultivars were harvested with all grades; first, extra, fancy and special. Group II cultivars generally had weaker stems and were of lower dry weight. Night air temperature had the greatest effect on days to harvest. Harvest date was reduced more than 14 days, but at the expense of quality and dry weight. Root-zone heating decreased quality of the group II cultivars at either night air temperature. but reduced quality of the group Ill cultivars only at high night temperatures. Root-zone heat and high night air temperature reduced the number of days to harvest, also at the expense of quality. The majority of high quality stems were from group Ill cultivars harvested from rooms with low night temperatures without root-zone heat.


Biologia ◽  
2014 ◽  
Vol 69 (11) ◽  
Author(s):  
Miloslav Šír ◽  
Miroslav Tesař ◽  
Ľubomír Lichner ◽  
Henryk Czachor

AbstractOscillations of the air temperature and tensiometric pressure of the soil water were measured in the experimental slope Tomšovka (Czech Republic, Jizera Mts, 822 m a.s.l.). The brown forest soil (Dystric Cambisols) is covered with Calamagrostis villosa, Avenella flexuosa and Vaccinium myrtilus. Thermometers were placed at a height of 5 and 200 cm above the grassland. The tensiometer was installed in the root zone of grass at a depth of 15 cm. Oscillations in a cloudless day, August 24, 2001, (sunshine duration 12.1 hour/day, daily total of global radiation 22.4 MJ/m2/day, maximum intensity of global radiation 1008 W/m2, transpiration 13.7 MJ/m2/day) were analysed in detail. The oscillations with a period of about 30 to 60 minutes were recorded in the air temperature course taken from 11 am to 5 pm. At the height of 200 cm oscillations ranged from 24 to 28°C. Concurrently, in the depth of 15 cm, the oscillations of tensiometric pressure in the range of −6 to −11 kPa were recorded from 8 am to 4 pm. It was concluded that the oscillations in the air temperature resulted from autonomous and self-regulated oscillations in the intensity of transpiration. It is evident that the 2-m air temperature was significantly influenced by transpiration of plants around the large area. The fact that the air temperature oscillated sharply confirms that the rate of transpiration was synchronized in this area. Vegetative cover thus created a self-regulated superorganism that substantially affected the temperature of the near-ground atmosphere layer.


2008 ◽  
Vol 95 (6) ◽  
pp. 659-668 ◽  
Author(s):  
Taisheng Du ◽  
Shaozhong Kang ◽  
Jianhua Zhang ◽  
Fusheng Li ◽  
Boyuan Yan

1959 ◽  
Vol 16 (6) ◽  
pp. 791-794 ◽  
Author(s):  
R. H. Moyer ◽  
B. A. Southcott ◽  
E. G. Baker ◽  
H. L. A. Tarr

Pacific coast dogfish (Squalus suckleyi) were held 21 days in ice and in refrigerated sea water with and without added chlortetracycline, viable bacterial counts and volatile bases being determined periodically. Viable bacteria increased sharply after about 14 days but the muscle pH values showed little or no increase. No appreciable increase in the total volatile base or trimethylamine content of the muscle was noted until the fish were stored for more than 2 weeks, and then the increases observed were comparatively small.


Sugar Tech ◽  
2012 ◽  
Vol 15 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Dilip Kumar ◽  
Jarnail Singh ◽  
D. R. Rai ◽  
Mahesh Kumar ◽  
S. Bhatia

1958 ◽  
Vol 25 (1) ◽  
pp. 32-51 ◽  
Author(s):  
Peggy B. Taylor ◽  
L. F. L. Clegg

The determination of apparent lactic acid has been used as a basis for a rejection test for raw milk. The method consists of precipitation of milk proteins with barium chloride, sodium hydroxide and zinc sulphate, and the addition of ferric chloride to the filtrate to produce the yellow colour of ferric lactate. Lactic acid is not solely responsible for the production of the yellow colour, which, nevertheless, gives a good relationship with keeping quality of milk (measured as hours to the C.O.B. end-point at 22° C.) and the values have been expressed as ‘apparent lactic acid’.The relationship of winter and summer milks to keeping quality has been studied, and a value of 0·03% apparent lactic acid in milk is equivalent to an average keeping quality of 5¾ and 8½ hr. for winter and summer milks, respectively. A value of 0·03% is recommended as the earliest value of apparent lactic acid at which milk could be rejected.The apparent lactic acid in colostrum and late-lactation milk and in milk from cows suffering from mastitis has been determined, and only in late-lactation milk were the values found to be significantly higher than usual in fresh raw milk, and an inverse relationship between yield and apparent lactic acid is suggested.Permanent glass matching disks have been prepared for use in a Lovibond comparator. This permits the intensity of the yellow colour produced with 1% ferric chloride to be determined and the apparent lactic acid in milk estimated.Grateful acknowledgement is made to the management and staff of the Dairy Department of the Reading Co-operative Society and the Farmer's Clean Milk Dairy, Reading, and local milk producers for supplying samples for experiments; to the N.M.T.S. staff in Reading for help in finding suitable farmers, and to the Dairy Husbandry Department of the N.I.R.D. for information about and samples of abnormal and late-lactation milk. Our particular thanks are due Miss Marie Gruber for technical assistance, to Dr N. J. Berridge for the suggestion and help on the work on pH change as an indication of keeping quality (given in the appendix), and to Dr A. T. R. Mattick for the advice given in this work.


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