Foliar Indicators and Sweet Cherry Production Efficiency in Central Leader and Kym Green Bush Training Systems in Chile

Figures & data

Table 1. Climatic variables during the evaluated season for Curicó and Pencahue, Chile

Season	Period	Variable	Curicó	Pencahue
Rest	May-Jul 2017	Mean air T (°C)	7.7	8.4
		Chill Hours (<7°C)	905	831
		Chill Units (Modified Utah model)	1,346	1,157
		Positive Chill Units (Positive Utah model)	1,390	1,293
		Rain (mm)	335.2	397.5
Fruit Growing Season	Sep-Dec 2017	Mean air T (°C)	13.6	14.7
		GDH	30,865	32,830
		GDD (base T, 10°C)	704	855
		Rain (mm)	209.2	280.6

Table 2. Background of the sweet cherry cultivars plantation used in the study

Location	Training system	Cultivar	Rootstock	Tree spacing (m)	Tree density (tree ha^−1)	Year planted	Height (m)
Curicó	CL	‘Lapins’	‘Colt’	4.5 × 2.5	889	2012	3.6
		‘Sweetheart’	‘Cab-6P’	4.5 × 2.5	889	2010	3.5
		‘Regina’	‘Maxma-14’	4.5 × 2.5	889	2010	3.2
Pencahue	KGB	‘Lapins’	‘Colt’	4.25 × 2.2	1,070	2011	3.7
		‘Bing’	‘Gisela-12’	4.25 × 2.0	1,176	2011	3.5

Figure 1. Sweet cherry tree ‘Lapins’, ‘Sweetheart’ and ‘Regina’ formed in CL (above) before manual defoliation and (below) after manual defoliation. Curicó, Chile

Figure 2. Sweet cherry ‘Bing’ and ‘Lapins’ formed in KGB (above) before manual defoliation and (below) after manual defoliation. Pencahue, Chile

Table 3. Foliar indicators for the sweet cherry cultivar/rootstock combinations according to training system (CL and KGB). Leaf samples were taken 125 days after full bloom

		Leaf					Tree
Cultivar	Trees per ha	LW (g)	LWD (g)	DML (%)	LA (cm^2)		LWT (kg)	LWDT (kg)	LNT	LAT (m^2)	LW/A (mg cm^−2)	LAI
CL
‘Lapins’/‘Colt’	889	1.3	0.53	41	53		5.5	2.2	4,230	22	25	2.0
‘Sweetheart’/‘Cab6’	889	1.3	0.48	38	46		6.4	2.4	5,140	24	28	2.1
‘Regina’/‘M14’	889	1.4	0.54	39	59		5.0	2.0	3,640	21	24	1.9
KGB
‘Lapins’/‘Colt’	1,070	1.2	0.46	38	63		6.7	2.6	5,590	35	19	3.7
‘Bing’/‘G12’	1,176	1.6	0.64	41	59		9.2	3.7	5,820	34	27	4.1

LW: Leaf weight; LWD: Leaf dry weight; DML: Leaf dry matter; LA: Leaf area; LWT: Leaf weight per tree; LWDT: Leaf dry weight per tree; LNT: Leaf number per tree; LAT: Leaf area per tree; LW/A: Leaf weight per leaf area; LAI: Leaf area index.

Table 4.. Production efficiency indicators for the sweet cherry cultivar/rootstock combinations according to training system (CL and KGB). Leaf samples were taken 125 days after full bloom

Cultivar	Trees per ha	Yield ha^−1 (t ha^−1)	Yield tree^−1 (kg)	LW ha^−1 (t ha^−1)	LWD ha^−1 (t ha^−1)	LA ha^−1 (m^2 ha^−1)	Yield/LA (kg m^−2)	LW/F (g fruit^−1)	LN/F (n° fruit^−1)	LA/F (cm^2 fruit^−1)
CL
‘Lapins’/‘Colt’	889	10.7	12.0	4.9	2.0	19,750	0.54	4.5	3.5	185
‘Sweetheart’/‘Cab6’	889	13.0	14.6	5.7	2.2	20,930	0.66	4.4	3.5	161
‘Regina’/‘M14’	889	8.7	9.8	4.5	1.7	18,860	0.46	5.1	3.7	217
KGB
‘Lapins’/‘Colt’	1,070	16.2	15.1	7.1	2.7	37,420	0.44	4.4	3.7	231
‘Bing’/‘G12’	1,176	19.7	16.8	10.8	4.4	40,570	0.49	5.5	3.5	206

Yield per hectare (Yield ha⁻¹); Yield per tree (Yield tree⁻¹); Leaf weight per hectare (LW ha⁻¹); Leaf dry weight per hectare (LWD ha⁻¹); Leaf area per hectare (LA ha⁻¹); Yield per leaf area (Yield/LA); Leaf weight per fruit (LW/F); Leaf number per fruit (LN/F); Leaf area per fruit (LA/F).

Figure 3. Principal component analysis based on foliar and productive efficiency indicators in sweet cherry trees. a: scores plot with Hotelling’s T² ellipse for cultivar/rootstock combinations and training system clusters (CL system: blue inner ellipse on II and III quadrant; KGB system: green inner ellipse on I and IV quadrant). b: correlations loadings show the most importance variables for the model. The outer ellipse indicates 100% explained variance and the inner ellipse indicates 50% of explained variance. DML: Leaf dry matter; LW: Leaf weight; LWD: Leaf dry weight; LWT: Leaf weight per tree; LWDT: Leaf dry weight per tree; LNT: Leaf number per tree; LA: Leaf area; LAT: Lear area per tree; LW/A: Leaf weight per leaf area; LAI: Leaf area index; Yield ha⁻¹: Yield per hectare; Yield tree⁻¹: Yield per tree; LN/F: Leaf number leaves per fruit; LW/F: Leaf weight per fruit; LA/F: Lear area per fruit; LW ha⁻¹: Leaf weight per hectare; LWD ha⁻¹: Leaf dry weight per hectare; LA ha⁻¹: Leaf area per hectare; Yield/LA: Yield per leaf area

Table 5.. Foliar and productive efficiency indicators in sweet cherry trees ‘Lapins’/‘Colt’ conducted in CL and KGB

Cultivar	LWT (kg)	LWDT (kg)	LAT (m^2)	LAI	LW/A (mg cm^−2)	LW ha^−1 (t)	LWD ha^−1 (t)	Yield/LA (kg m^−2)	LA/F (cm^2)
CL	5.5	2.2	22	2.0	25	4.9	2.0	0.54	185
KGB	6.7	2.6	35	3.7	19	7.1	2.7	0.44	231
Significance	ns	ns	*	**	**	*	ns	ns	ns
P value	0.18	0.37	0.03	0.01	0.00	0.04	0.09	0.12	0.13

Significant differences according to Tukey test. *P ≤ 0.05; ** P ≤ 0.01; ns = no significative

LWT: Leaf weight per tree; LWDT: Leaf dry weight per tree; LAT: Lear area per tree; LAI: Leaf area index; LW/A: Leaf weight per leaf area; LW ha⁻¹: Leaf weight per hectare; LWD ha⁻¹: Leaf dry weight per hectare; Yield/LA: Yield per leaf area; LA/F: Leaf area per fruit.