Effect of Humic Acid, Nitrogen Concentrations and Application Method on the Morphological, Yield and Biochemical Characteristics of Strawberry ‘Paros’

Figures & data

Table 1. Results of soil degradation and animal manure test used.

characteristics	Ec	pH	Lime	Organic carbon	Total nitrogen	Sand	Clay	Silt	P	K	Zn	Fe	Cu	Mn
	M S/cm		%						ppm
animal manure	21.30	7.85	8.24	11.15	1.10	0	0	0	126	23775	58.70	57.06	2.80	46.06
Soil	2.18	7.42	14.13	14.13	0.13	48	14	38	15.26	822	8.77	1.11	1.14	7.39

Table 2. Mean comparison of interaction effects of humic acid levels and application methods on leaf area and chlorophyll a.

T. Application methods	T. Humic acid (kg ha^−1)	Leaf area (cm^2)	Chlorophyll a (mg g fw^−1)
Foliar	0	920.14^cd	1.89^ab
	2	1050.28^bc	2.04^a
	4	1128.23^abc	1.92^ab
	6	768.75^d	1.50 ^c
Soil	0	915.16 ^cd	1.73^bc
	2	1013.77 ^c	1.88^ab
	4	1250.43^ab	1.93^ab
	6	1304.34^a	1.68^bc
CV%		18.70	10.04
LSD 5%		325.02	0.30

Different letters indicate significant differences were observed using the LSD test at 5% probability level.

mg g fw⁻¹: milligram per gram of fresh leaf biomass

Table 3. Mean comparison of interaction of nitrogen and humic acid on area, chlorophyll a and carotenoids of leaf,yield and total acidity of fruit.

T. Nitrogen (kg ha^−1)	T. Humic acid (kg ha^−1)	Leaf area (cm^2)	fruit yield (g m^2)	Chlorophyll a (mg g fw^−1)	Carotenoids (mg g fw^−1)	Total acidity of fruit (TA) (%)
50	0	864.60^b	300.48^e	1.66 ^c	0.23^bc	1.19^def
	2	980.33^b	426.40^e	1.88^b	0.28^b	1.32^cde
	4	1140.75^b	623.12^bc	1.97^b	0.36^a	1.56^bc
	6	1084.16^b	264.16^e	1.65 ^c	0.26^bc	1.11^ef
100	0	1005.11^b	390.08^de	1.93^b	0.35^a	1.43^bcd
	2	1075.40^b	504.48 ^cd	2.07^ab	0.36^a	1.61^a
	4	1491.53^a	835.44^a	2.23^a	0.37^a	1.88^a
	6	1115.56^b	675.76^abc	1.82^bc	0.22 ^c	1.06^ef
150	0	883.25^b	716.96^ab	1.89^b	0.27^b	1.00^f
	2	1040.36^b	753.36^ab	1.92^b	0.25^bc	1.23^def
	4	935.71^b	409.12^de	1.58 ^cd	0.24^bc	1.14^ef
	6	909.91^b	251.92^e	1.35^d	0.15^d	1.04^f
CV %		18.70	27.60	10.04	15.70	15.60
LSD 5%		325.02	188.72	0.30	0.07	0.34

Different lettersindicate significant differences were observed using the LSD test at 5% probability level.

mg g fw⁻¹: milligram per gram of fresh leaf weight

Table 4. Mean comparison of the three – wayinteraction between different levels of nitrogen, humic acid and methods of their application on shoot and root biomass, total chlorophyll, nitrogen and protein of leaf and root, total soluble solids and ascorbic acid of fruit.

T. Nitrogen (kg ha^−1)	T. Application methods	T. Humic acid (kg ha^−1)	Dry weight (g m^2)		Total chlorophyll (mg g fw^−1)	Nitrogen (%)		Protein (%)		Total soluble solids (TSS) (^0Brix)	Ascorbic acid (mg 100 g fw^−1)
			shoot	root		leaf	root	leaf	root
50	Foliar	0	68.64^ij	60.00^i	2.20^ijk	0.88 ^m	0.73 ^m	5.49 ^m	4.55 ^m	5.96 ^l	32.53^jk 35.06^ij 37.70^i 36.23^i
		2	82.16^ghi	64.64^hi	2.50^defgh	0.99 ^l	0.77 ^lm	6.22 ^l	4.80 ^lm	6.73^kl
		4	152.00^ab	112.00^b	2.59^cdefg	1.11^kl	1.05^ghijk	6.97^kl	6.55^ghijk	8.44^ghij
		6	35.12 ^l	39.60 ^j	2.28^fghijk	1.18^k	1.12^fghij	7.39^k	7.04 ^fghij	9.68^cdefg
	Soil	0	74.64^hij	58.64^i	1.95^jk	1.32 ^j	0.77 ^lm	8.26 ^j	4.81 ^lm	5.93 ^l	32.03^jk 35.03^ij
		2	123.52 ^cd	83.76^defg	2.52^defgh	1.44^hij	0.93^jkl	8.99^hij	5.85^jkl	7.73^ijk
		4	70.88^ij	90.56^cdef	2.69^abcde	1.46^hi	1.13^fghi	9.14^hi	7.08^fghi	8.86^fghi	45.53^g 54.07 ^cd
		6	53.52^jkl	60.56^i	2.25^ghijk	1.83^d	1.00^hijk	11.43^d	6.26^hijk	8.42^ghij
100	Foliar	0	101.20^defg	62.72^hi	2.60^cdefg	1.06^kl	0.96^ijk	6.66^kl	5.99^ijk	8.16^hij	55.02 ^cd
		2	110.96^def	92.08^cde	2.95^ab	1.76^de	1.07^ghij	11.04^de	6.68^ghij	9.56^defg	64.20^a
		4	168.64^a	130.24^a	3.02^a	2.37^b	1.33^cde	14.80^b	8.35^cde	10.53^abcd	49.63^ef 30.53^k
		6	105.92^defg	81.20^defgh	2.08^ijk	1.82^d	1.19^efgh	11.35^d	7.45^efgh	9.39^defgh
	Soil	0	116.32^cde	73.20^fghi	2.47^defgh	1.39^ij	1.22^defg	8.72^ij	7.66^defg	9.68^cdefg	41.06 ^h 48.48^fg
		2	117.60^cde	94.80^bcde	2.68^abcde	1.34^ij	1.33^cde	8.37^ij	8.30^cde	9.90^bcdef
		4	161.04^ab	99.04^bcd	2.94^abc	1.43^hij	1.40^bcd	8.93^hij	8.76^bcd	10.90^abc	57.24^bc
		6	95.68^efgh	64.24^hi	2.82^abcd	1.86^d	1.10^ghij	11.62^d	6.87^ghij	11.57^a	60.19^b
150	Foliar	0	53.92^jkl	62.88^hi	2.62^bcdef	1.53 ^gh	1.44^abc	9.58^gh	9.02^abc	7.28^jk	36.07^i 52.98^de
		2	97.76^efgh	68.08^ghi	2.83^abcd	2.54^a	1.23^defg	15.89^a	7.68^defg	8.40^ghij
		4	138.72^bc	79.52^efgh	2.27^fghijk	2.24 ^c	1.08^ghij	14.04 ^c	6.76^ghij	9.16^efgh	41.03 ^h 25.00 ^l
		6	43.52^kl	33.920 ^j	1.94^k	1.15^k	0.87^klm	7.18^k	5.43^klm	8.50^ghij
	Soil	0	64.80^ijk	38.64 ^j	2.38^efghi	1.62^fg	1.60^a	10.16^fg	10.01^a	7.31^jk	35.00^ij 47.00 ^fg 50.13^ef 32.00^jk
		2	86.24^fghi	60.40^i	2.42^efghi	1.67^ef	1.54^ab	10.45^ef	9.62^ab	9.51^defg
		4	98.72^defgh	79.92^efgh	2.29^fghij	1.81^d	1.30^cdef	11.33^d	8.14 ^cdef	11.07^ab
		6	161.36^ab	105.44^bc	1.93^k	2.18 ^c	1.30^cdef	13.66 ^c	8.12^cdef	10.41^abcde
CV %			14.20	13.50	7.50	4.40	8.60	4.50	8.60	7.98	4.90
LSD 5%			23.36	16.80	0.36	0.12	0.17	0.74	1.03	1.18	3.57

Different lettersindicate significant differences were observed using the LSD test at 5% probability level.

mg g fw⁻¹: milligram per gram of fresh leaf weight, mg 100 g fw⁻¹: milligram per 100 gram of fresh fruit weight

Table 5. Mean comparison of different levels of nitrogen on chlorophyll b leaf and fruit acidity.

T. Nitrogen (kg ha^−1)	Chlorophyll b (mg g fw^−1)	Fruit acidity (pH)
50	0.61^b	4.03^a
100	0.68^a	3.86^ab
150	0.64^ab	3.73^b
CV %	10.20	8.27
LSD 5%	0.05	0.30

Different lettersindicate significant differences, which were observed using the LSD test at the 5% probability level.

mg g fw⁻¹: milligram per gram of fresh leaf weight

Table 6. Mean comparison of different levels of humic acid on chlorophyll b leaf and fruit acidity.

T. Humic acid (kg ha^−1)	Chlorophyll b (mg g fw^−1)	Fruit acidity (pH)
0	0.58^b	4.03^a 3.86^a
2	0.68^a
4	0.70^a	3.62^b
6	0.62^b	3.98^a
CV %	10.20	8.27
LSD 5%	0.03	0.18

Different lettersindicate significant differences were observed using the LSD test at 5% probability level.

mg g fw⁻¹: milligram per gram of fresh leaf weight